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Reading Section
THE GREENHOUSE EFFECT AND GLOBAL WARMING Carbon dioxide and other naturally occurring gases in the earth’s atmosphere create a natural greenhouse effect by trapping and absorbing solar radiation. These gases act as a blanket and keep the planet warm enough for life to survive and flourish. The warming of the earth is balanced by some of the heat escaping from the atmosphere back into space. Without this compensating flow of heat out of the system, the temperature of the earth’s surface and its atmosphere would rise steadily. Scientists are increasingly concerned about a human-driven greenhouse effect resulting from a rise in atmospheric levels of carbon dioxide and other heat-trapping greenhouse gases. The man-made greenhouse effect is the exhalation of industrial civilization. A major contributing factor is the burning of large amounts of fossil fuels—coal, petroleum, and natural gas. Another is the destruction of the world’s forests, which reduces the amount of carbon dioxide converted to oxygen by plants. Emissions of carbon dioxide, chlorofluorocarbons. nitrous oxide, and methane from human activities will enhance the greenhouse effect, causing the earth’s surface to become warmer. The main greenhouse gas, water vapor, will increase in response to global warming and further enhance it. There is agreement within the scientific community that the buildup of greenhouse gases is already causing the earth’s average surface temperature to rise. This is changing global climate at an unusually fast rate. According to the World Meteorological Organization, the earth’s average temperature climbed about 1 degree F in the past century, and nine of the ten warmest years on record have occurred since 1990. A United Nations panel has predicted that average global temperatures could rise as much as 10.5 degrees F during the next century as heat-trapping gases from human industry accumulate in the atmosphere. What are the potential impacts of an enhanced greenhouse effect? According to estimates by an international committee, North American climatic zones could shift northward by as much as 550 kilometers (340 miles). Such a change in climate would likely affect all sectors of society. In some areas, heat and moisture stress would cut crop yields, and traditional farming practices would have to change. For example, in the North American grain belt, higher temperatures and more frequent drought during the growing season might require farmers to switch from corn to wheat and to use more water for irrigation. Global warming may also cause a rise in sea level by melting polar ice caps. A rise in sea level would accelerate coastal erosion and inundate islands and low-lying coastal plains, some of which are densely populated. Millions of acres of coastal farmlands would be covered by water. Furthermore, the warming of seawater will cause the water to expand, thus adding to the potential danger. Global warming has already left its fingerprint on the natural world. Two research teams recently reviewed hundreds of published papers that tracked changes in the range and behavior of plant and animal species, and they found ample evidence of plants blooming and birds nesting earlier in the spring. Both teams concluded that rising global temperatures are shifting the ranges of hundreds of species—thus climatic zones—northward. These studies are hard evidence that the natural world is already responding dramatically to climate change, even though the change has just begun. If global warming trends continue, changes in the environment will have an enormous impact on world biology. Birds especially play a critical role in the environment by pollinating plants, dispersing seeds, and controlling insect populations; thus, changes in their populations will reverberate throughout the ecosystems they inhabit.
| 1. According to the passage, how do carbon dioxide and other greenhouse gases affect the earth-atmosphere system? |
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They decrease the amount of oxygen in the atmosphere. |
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B. |
They create the conditions for new forms of life to emerge. |
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C. |
They cause heat to flow from the atmosphere into space. |
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D. |
They collect solar radiation that warms the earth's surface. |
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Explain: |
| 2. All of the following are contributing factors to global warming EXCEPT ................ |
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A. |
the loss of forest lands |
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B. |
the burning of coal and petroleum |
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C. |
the conversion of carbon dioxide to oxygen |
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D. |
the buildup of water vapor in the atmosphere |
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Explain: |
| 3. The word “enhance” in paragraph 2 is closest in meaning to ................ |
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| 4. What can be inferred from paragraph 3 about global climate change? |
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Climate change is likely to continue as long as heat-trapping gases accumulate. |
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B. |
It is difficult to predict the effects of climate change over the next century. |
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C. |
Climate change will have both positive and negative effects on human society. |
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International organizations have been studying climate change only since 1990. |
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Explain: |
| 5. According to paragraph 4, what is one effect that climate change could have on agriculture in North America? |
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Less water available for irrigating crops |
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B. |
Return to more traditional methods of farming |
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Movement of farms to the northernmost regions |
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D. |
Changes in the crops that farmers can grow |
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Explain: |
| 6. The word “inundate” in paragraph 5 is closest in meaning to ................ |
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| 7. Why does the author use the word “fingerprint” in paragraph 6? |
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To suggest that people do not cause global warming |
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To introduce conclusive evidence of global warming |
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To describe a method used by two research teams |
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To show that hundreds of fingerprints were examined |
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Explain: |
| 8. The word “they” in paragraph 6 refers to ................ |
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| 9. The word “hard” in paragraph 6 is closest in meaning to ................ |
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| 10. What evidence does the author give that climatic zones have shifted northward? |
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Solar radiation escapes from the atmosphere back into space. |
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B. |
Birds no longer pollinate plants or control insect populations. |
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The water in the ocean expands as it gets warmer. |
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Plants bloom and birds build nests earlier in the spring. |
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Explain: |
| 11. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “The combination of melting ice caps with the expansion of water could raise the sea level several centimeters by the year 2100.” could be added to the passage. Where would the sentence best fit? |
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| 12. An introductory sentence for a brief summary of the passage is: “Scientists are concerned about the greenhouse effect and its role in global warming.” Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. |
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Nine of the ten warmest years on record have occurred since 1990. |
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Global warming will alter the range and behavior of plants and animals, changing the balance of ecosystems. |
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A rising sea level and shifts in climatic zones are probable effects of global warming. |
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Some scientists think the temperature trend indicates man-made global warming, while others believe it is natural climate variability. |
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Global warming could result in job loss for millions of farmers in coastal areas. |
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A rise in atmospheric levels of carbon dioxide and other greenhouse gases is causing the earth's surface to become warmer. |
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Explain: |
EARLY AUTOS America’s passion for the automobile developed rather quickly in the beginning of the twentieth century. At the turn of that century, there were few automobiles, or horseless carriages, as they were called at the time, and those that existed were considered frivolous playthings of the rich. They were rather fragile machines that sputtered and smoked and broke down often; they were expensive toys that could not be counted on to get one where one needed to go; they could only be afforded by the wealthy class, who could afford both the expensive upkeep and the inherent delays that resulted from the use of a machine that tended to break down time and again. These early automobiles required repairs so frequently both because their engineering was at an immature stage and because roads were unpaved and often in poor condition. Then, when breakdowns occurred, there were no services such as roadside gas stations or tow trucks to assist drivers needing help in their predicament. Drivers of horse-drawn carriages considered the horseless mode of transportation foolhardy, preferring instead to rely on their four-legged “engines,” which they considered a tremendously more dependable and cost-effective means of getting around. Automobiles in the beginning of the twentieth century were quite unlike today’s models. Many of them were electric cars, even though the electric models had quite a limited range and needed to be recharged frequently at electric charging stations; many others were powered by steam, though it was often required that drivers of steam cars be certified steam engineers due to the dangers inherent in operating a steam-powered machine. The early automobiles also lacked much emphasis on body design; in fact, they were often little more than benches on wheels, though by the end of the first decade of the century they had progressed to leather-upholstered chairs or sofas on thin wheels that absorbed little of the incessant pounding associated with the movement of these machines. In spite of the rather rough and undeveloped nature of these early horseless carriages, something about them grabbed people’s imagination, and their use increased rapidly, though not always smoothly. In the first decade of the last century, roads were shared by the horse-drawn and horseless variety of carriages, a situation that was rife with problems and required strict measures to control the incidents and accidents that resulted when two such different modes of transportation were used in close proximity. New York City, for example, banned horseless vehicles from Central Park early in the century because they had been involved in so many accidents, often causing injury or death; then, in 1904, New York state felt that it was necessary to control automobile traffic by placing speed limits of 20 miles per hour in open areas, 15 miles per hour in villages, and 10 miles per hour in cities or areas of congestion. However, the measures taken were less a means of limiting use of the automobile and more a way of controlling the effects of an invention whose use increased dramatically in a relatively short period of time. Under 5,000 automobiles were sold in the United States for a total cost of approximately $5 million in 1900, while considerably more cars, 181,000, were sold for $215 million in 1910, and by the middle of the 1920s, automobile manufacturing had become the top industry in the United States and accounted for 6 percent of the manufacturing in the country.
| 13. Based on the information in paragraph 1, who would have been most likely to own a car in 1900? ................ |
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Explain: |
| 14. The word “frivolous” in paragraph 1 is closest in meaning to ................ |
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Explain: |
| 15. It is indicated in paragraph 1 that it was necessary to repair early autos because of ................ |
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Explain: |
| 16. The author refers to “four-legged engines” in paragraph 1 in order to indicate that ................ |
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horses were an effective mode of transportation |
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automobile engines were evaluated in terms of their horsepower |
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it was foolish to travel on a four-legged animal |
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early autos had little more than an engine and wheels |
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Explain: |
| 17. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “These horrendous road conditions forced drivers to use their automobiles on grooved, rutted, and bumpy roads.” can be added to paragraph 1. Where would the sentence best fit? ................ |
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| 18. The phrase “many others” in paragraph 2 refers to ................ |
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B. |
electric charging stations |
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C. |
automobiles in the beginning of the twentieth century |
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Explain: |
| 19. It is stated in paragraph 2 that the owners of steam-powered cars ................ |
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often had to take their automobiles to charging stations |
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B. |
had to hire drivers to operate their cars |
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sometimes had to demonstrate knowledge of steam engineering |
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were often in danger because of the limited range of their automobiles |
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Explain: |
| 20. Why does the author mention “benches on wheels” in paragraph 2? ................ |
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To show that car designs of the time were neither complex nor comfortable |
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B. |
To show how remarkably automobile design had progressed |
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To emphasize how the early automobiles were designed to absorb the pounding of the machine on the road |
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D. |
To indicate that early automobiles had upholstered chairs or sofas |
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Explain: |
| 21. The word “incessant” in paragraph 2 is closest in meaning to ................ |
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Explain: |
| 22. The phrase “rife with” in paragraph 3 could be replaced by ................ |
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A. |
occurring as a result of |
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Explain: |
| 23. It can be inferred from paragraph 3 that the government of New York state believed that ................ |
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all horseless vehicles should be banned from all public parks |
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strict speed limits should be placed on horse-drawn carriages |
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horseless and horse-drawn vehicles should not travel on the same roads |
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it was safer for cars to travel faster where there was less traffic and fewer people |
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Explain: |
| 24. Which of the sentences below expresses the essential information in the highlighted sentence in paragraph 3? Incorrect choices change the meaning in important ways or leave out essential information. ................ |
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It was important to lawmakers to discover the causes of the problems relating to automobiles. |
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The dramatic look of the automobile changed considerably over a short period of time. |
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C. |
The various laws were needed because the use of automobiles grew so fast. |
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D. |
It was necessary to take a measured approach in dealing with inventions such as the automobile. |
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Explain: |
| 25. According to paragraph 3, it is NOT true that ................ |
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the total cost of the automobiles sold in the United States in 1900 was around $5 million |
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automobile manufacturing was the top U.S. industry in 1920 |
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sales of cars increased by more than 175,000 from 1900 to 1910 |
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D. |
automobile manufacturing represented more than 5 percent of total U.S. manufacturing by 1925 |
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Explain: |
PULSARS There is still much for astronomers to learn about pulsars. Based on what is known, the term pulsar is used to describe the phenomenon of short, precisely timed radio bursts that are emitted from somewhere in space. Though all is not known about pulsars, they are now believed in reality to emanate from spinning neutron stars, highly reduced cores of collapsed stars that are theorized to exist. Pulsars were discovered in 1967, when Jocelyn Bell, a graduate student at Cambridge University, noticed an unusual pattern on a chart from a radio telescope. What made this pattern unusual was that, unlike other radio signals from celestial objects, this series of pulses had a highly regular period of 1.33730119 seconds. Because day after day the pulses came from the same place among the stars, Cambridge researchers came to the conclusion that they could not have come from a local source such as an Earth satellite. (1) A name was needed for this newly discovered phenomenon. (2) The possibility that the signals were coming from a distant civilization was considered, and at that point the idea of naming the phenomenon L.G.M. (short for Little Green Men) was raised. (3) However, after researchers had found three more regularly pulsing objects in other parts of the sky over the next few weeks, the name pulsar was selected instead of L.G.M. (4) As more and more pulsars were found, astronomers engaged in debates over their nature. It was determined that a pulsar could not be a star inasmuch as a normal star is too big to pulse so fast. The question was also raised as to whether a pulsar might be a white dwarf star, a dying star that has collapsed to approximately the size of the Earth and is slowly cooling off. However, this idea was also rejected because the fastest pulsar known at the time pulsed around thirty times per second and a white dwarf, which is the smallest known type of star, would not hold together if it were to spin that fast. The final conclusion among astronomers was that only a neutron star, which is theorized to be the remaining core of a collapsed star that has been reduced to a highly dense radius of only around 10 kilometers, was small enough to be a pulsar. Further evidence of the link between pulsars and neutron stars was found in 1968, when a pulsar was found in the middle of the Crab Nebula. The Crab Nebula is what remains of the supernova of the year 1054, and inasmuch as it has been theorized that neutron stars sometimes remain following supernova explosions, it is believed that the pulsar coming from the Crab Nebula is evidently just such a neutron star. (5) The generally accepted theory for pulsars is the lighthouse theory, which is based upon a consideration of the theoretical properties of neutron stars and the observed properties of pulsars. (6) According to the lighthouse theory, a spinning neutron star emits beams of radiation that sweep through the sky, and when one of the beams passes over the Earth, it is detectable on Earth. (7) It is known as the lighthouse theory because the emissions from neutron stars are similar to the pulses of light emitted from lighthouses as they sweep over the ocean; the name lighthouse is therefore actually more appropriate than the name pulsar. (8)
| 26. The phrase “emanate from” in paragraph 1 is closest in meaning to ................ |
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D. |
receive directions from |
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Explain: |
| 27. Which of the sentences below expresses the essential information in the highlighted sentence in paragraph 2? Incorrect choices change the meaning in important ways or leave out essential information. ................ |
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A. |
It was unusual that the pattern of the pulsars was so regular. |
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B. |
It was unusual for celestial objects to emit radio signals. |
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C. |
It was unusual for researchers to hear patterns from space. |
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D. |
It was unusual that the period of pulses was only slightly more than a second in length. |
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Explain: |
| 28. The word “they” in paragraph 2 refers to ................ |
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Explain: |
| 29. The word “raised” in paragraph 3 could best be replaced by ................ |
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Explain: |
| 30. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “This name was selected because it indicates a regularly pulsing radio source.” can be added to paragraph 3. Where would the sentence best fit? ................ |
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Explain: |
| 31. The phrase “engaged in” in paragraph 4 could best be replaced by ................ |
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Explain: |
| 32. The word “their” in paragraph 4 refers to ................ |
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Explain: |
| 33. Which of the sentences below expresses the essential information in the highlighted sentence in paragraph 4? Incorrect choices change the meaning in important ways or leave out essential information. ................ |
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A. |
White dwarfs cannot contain pulsars because white dwarfs spin much faster than pulsars. |
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B. |
Pulsars cannot spin very fast because they will fall apart if they spin fast. |
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C. |
White dwarfs cannot be dying stars because they cannot pulse at around thirty times per second. |
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D. |
Pulsars could not be white dwarfs because the frequency of the pulsars is too high. |
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Explain: |
| 34. The word “Further” in paragraph 5 is closest in meaning to ................ |
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Explain: |
| 35. Which of the sentences below expresses the essential information in the highlighted sentence in paragraph 5? Incorrect choices change the meaning in important ways or leave out essential information. ................ |
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A. |
It is believed that the supernova of1054 created the Crab Nebula, which contains a pulsing neutron star. |
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B. |
It is believed that a neutron star exploded in the supernova of 1054, creating the Crab Nebula. |
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C. |
It is believed that a pulsar created the Crab Nebula, which exploded in a supernova in 1054. |
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D. |
It is believed that the Crab Nebula is a pulsar that is on the verge of becoming a supernova. |
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Explain: |
| 36. The word “properties” in paragraph 6 is closest in meaning to ................ |
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Explain: |
| 37. The word “it” in paragraph 6 refers to ................ |
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B. |
a spinning neutron star |
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Explain: |
| 38. Look at the four numbers (5), (6), (7) and (8) which indicate where the sentence “The periodic flashing of pulsars is related to rotation rather than pulsing, so the name pulsar is actually not very accurate.” can be added to paragraph 6. Where would the sentence best fit? ................ |
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Explain: |
CARETAKER SPEECH Children learn to construct language from those around them. Until about the age of three, children tend to learn to develop their language by modeling the speech of their parents, but from that time on, peers have a growing influence as models for language development in children. It is easy to observe that, when adults and older children interact with younger children, they tend to modify their language to improve communication with younger children, and this modified language is called caretaker speech. Caretaker speech is used often quite unconsciously; few people actually study how to modify language when speaking to young children but, instead, without thinking, find ways to reduce the complexity of language in order to communicate effectively with young children. (1) A caretaker will unconsciously speak in one way with adults and in a very different way with young children. (2) Caretaker speech tends to be slower speech with short, simple words and sentences which are said in a higher-pitched voice with exaggerated inflections and many repetitions of essential information. (3) It is not limited to what is commonly called baby talk, which generally refers to the use of simplified, repeated syllable expressions such as ma-ma, boo-boo, bye-bye, wa-wa, but also includes the simplified sentence structures repeated in sing-song inflections. (4) Caretaker speech serves the very important function of allowing young children to acquire language more easily. The higher-pitched voice and the exaggerated inflections tend to focus the small child on what the caretaker is saying, the simplified words and sentences make it easier for the small child to begin to comprehend, and the repetitions reinforce the child’s developing understanding. Then, as a child’s speech develops, caretakers tend to adjust their language in response to the improved language skills, again quite unconsciously. Parents and older children regularly adjust their speech to a level that is slightly above that of a younger child; without studied recognition of what they are doing, these caretakers will speak in one way to a one-year-old and in a progressively more complex way as the child reaches the age of two or three. (1) An important point to note is that the function covered by caretaker speech, that of assisting a child to acquire language in small and simple steps, is an unconsciously used but extremely important part of the process of language acquisition and as such is quite universal. (2) Studying cultures where children do not acquire language through caretaker speech is difficult because such cultures are difficult to find. (3) The question of why caretaker speech is universal is not clearly understood; instead proponents on either side of the nature vs. nurture debate argue over whether caretaker speech is a natural function or a learned one. (4) Those who believe that caretaker speech is a natural and inherent function in humans believe that it is human nature for children to acquire language and for those around them to encourage their language acquisition naturally; the presence of a child is itself a natural stimulus that increases the rate of caretaker speech among those present. In contrast, those who believe that caretaker speech develops through nurturing rather than nature argue that a person who is attempting to communicate with a child will learn by trying out different ways of communicating to determine which is the most effective from the reactions to the communication attempts; a parent might, for example, learn to use speech with exaggerated inflections with a small child because the exaggerated inflections do a better job of attracting the child’s attention than do more subtle inflections. Whether caretaker speech results from nature or nurture, it does play an important and universal role in child language acquisition.
| 39. According to paragraph 1, children over the age of three ................ |
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learn little language from those around them |
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B. |
first begin to respond to caretaker speech |
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C. |
are influenced more and more by those closer to their own age |
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D. |
are no longer influenced by the language of their parents |
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Explain: |
| 40. The word “modeling” in paragraph 1 could best be replaced by ................ |
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Explain: |
| 41. Which of the sentences below expresses the essential information in the highlighted sentence in paragraph 2? Incorrect choices change the meaning in important ways or leave out essential information. ................ |
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A. |
The unconscious use of caretaker speech involves a reduction in the complexity of language, while the conscious use of caretaker speech involves an increase in complexity. |
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B. |
People generally seem to be able to adapt their language to the level of a child's language without thinking consciously about it. |
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C. |
Young children tend to use caretaker speech quite unconsciously in order to reduce the complexity of their thoughts to language that they can express. |
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D. |
Most people are quite aware of the use of caretaker speech because of thorough study and research about it. |
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Explain: |
| 42. The word “It” in paragraph 2 refers to ................ |
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B. |
a higher-pitched voice |
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Explain: |
| 43. Look at the four numbers (1), (2), (3) and (4) in paragraph 2 which indicate where the sentence “Examples of these are expressions such as “Say bye-bye” or “Where′s da-da?”” can be added to paragraph 2. Where would the sentence best fit? ................ |
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Explain: |
| 44. All of the following are mentioned in paragraph 3 as characteristics of caretaker speech EXCEPT ................ |
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the use of easier words and structures |
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B. |
overemphasized inflections |
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the use of rhyming sounds |
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D. |
the tendency to repeat oneself |
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Explain: |
| 45. It is indicated in paragraph 3 that parents tend to ................ |
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speak in basically the same way to a one-year-old and a three-year-old |
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B. |
modify their speech according to the language development of a child |
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C. |
use language that is far above the language level of a child |
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D. |
speak in a progressively less complex way as a child matures |
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Explain: |
| 46. The word “reaches” in paragraph 3 could best be replaced by ................ |
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Explain: |
| 47. The word “that” in paragraph 4 refers to ................ |
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Explain: |
| 48. Which of the sentences beiow expresses the essential information in the highlighted sentence in paragraph 4? Incorrect choices change the meaning in important ways or leave out essential information. ................ |
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A. |
Caretaker speech is one of many natural functions that are used to stimulate young children to develop more rapidly. |
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B. |
People who believe in nature over nurture feel that adults or older children who are around younger children will naturally make changes in their language. |
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C. |
The natural human tendency to acquire language makes caretaker speech unimportant in improving the rate of language acquisition by children. |
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D. |
It is human nature for children to develop the use of caretaker speech in order to take part effectively in conversations around them. |
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Explain: |
| 49. According to paragraph 4, it is NOT expected that someone who believes in nurture over nature ................ |
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A. |
would learn to use different styles of caretaker speech with different children |
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B. |
would believe that caretaker speech is more of a learned style of language - than a natural one |
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C. |
would use different styles of caretaker speech with children in response to what is working best |
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D. |
would use less caretaker speech than do those who believe in nature over nurture |
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Explain: |
| 50. The phrase “trying out” in paragraph 4 is closest in meaning to ................ |
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Explain: |
| 51. Look at the four numbers (1), (2), (3) and (4) in paragraph 4 which indicate where the sentence “It is not merely a device used by English-speaking parents.” can be added to paragraph 4. Where would the sentence best fit? ................ |
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FEEDING HABITS OF EAST AFRICAN HERBIVORES Buffalo, zebras, wildebeests, topi, and Thomson's gazelles live in huge groups that together make up some 90 percent of the total weight of mammals living on the Serengeti Plain of East Africa. They are all herbivores (plant-eating animals), and they all appear to be living on the same diet of grasses, herbs, and small bushes. This appearance, however, is illusory. When biologist Richard Bell and his colleagues analyzed the stomach contents of four of the five species (they did not study buffalo), they found that each species was living on a different part of the vegetation. The different vegetational parts differ in their food qualities: lower down, there are succulent, nutritious leaves; higher up are the harder stems. There are also sparsely distributed, highly nutritious fruits, and Bell found that only the Thomson's gazelles eat much of these. The other three species differ in the proportion of lower leaves and higher stems that they eat: zebras eat the most stem matter, wildebeests eat the most leaves, and topi are intermediate. How are we to understand their different feeding preferences? The answer lies in two associated differences among the species, in their digestive systems and body sizes. According to their digestive systems, these herbivores can be divided into two categories: the nonruminants (such as the zebra, which has a digestive system like a horse) and the ruminants (such as the wildebeest, topi, and gazelle, which are like the cow). Nonruminants cannot extract much energy from the hard parts of a plant; however, this is more than made up for by the fast speed at which food passes through their guts. Thus, when there is only a short supply of poor-quality food, the wildebeest, topi, and gazelle enjoy an advantage. They are ruminants and have a special structure (the rumen) in their stomachs, which contains microorganisms that can break down the hard parts of plants. Food passes only slowly through the ruminant's gut because ruminating—digesting the hard parts—takes time. The ruminant continually regurgitates food from its stomach back to its mouth to chew it up further (that is what a cow is doing when "chewing cud"). Only when it has been chewed up and digested almost to a liquid can the food pass through the rumen and on through the gut. Larger particles cannot pass through until they have been chewed down to size. Therefore, when food is in short supply, a ruminant can last longer than a nonruminant because it can derive more energy out of the same food. The difference can partially explain the eating habits of the Serengeti herbivores. The zebra chooses areas where there is more low-quality food. It migrates first to unexploited areas and chomps the abundant low-quality stems before moving on. It is a fast-in/fast-out feeder, relying on a high output of incompletely digested food. By the time the wildebeests (and other ruminants) arrive, the grazing and trampling of the zebras will have worn the vegetation down. As the ruminants then set to work, they eat down to the lower, leafier parts of the vegetation. All of this fits in with the differences in stomach contents with which we began. The other part of the explanation is body size. Larger animals require more food than smaller animals, but smaller animals have a higher metabolic rate. Smaller animals can therefore live where there is less food, provided that such food is of high energy content. That is why the smallest of the herbivores, Thomson's gazelle, lives on fruit that is very nutritious but too thin on the ground to support a larger animal. By contrast, the large zebra lives on the masses of low-quality stem material. The differences in feeding preferences lead, in turn, to differences in migratory habits. (1) The wildebeests follow, in their migration, the pattern of local rainfall. (2) The other species do likewise. (3) But when a new area is fueled by rain, the mammals migrate toward it in a set order to exploit it. (4) The larger, less fastidious feeders, the zebras, move in first; the choosier, smaller wildebeests come later; and the smallest species of all, Thomson's gazelle, arrives last. The later species all depend on the preparations of the earlier one, for the actions of the zebra alter the vegetation to suit the stomachs of the wildebeest, topi, and gazelle.
| 52. The word “illusory” in the passage is closest in meaning to ................ |
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| 53. The word “sparsely” in the passage is closest in meaning to ................ |
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| 54. Which of the following questions about Richard Bell′s research is NOT answered in paragraph 1? |
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Why were buffalo excluded from the research study? |
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Which of the herbivores studied is the only one to eat much fruit? |
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Which part of the plants do wildebeests prefer to eat? |
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Where did the study of herbivores' eating habits take place? |
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| 55. The word "associated” in the passage is closest in meaning to ................ |
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| 56. The author mentions the cow and the horse in paragraph 2 in order to |
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emphasize similarities between the diets of cows and horses and the diets of East African mammals |
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distinguish the functioning of their digestive systems from those of East African mammals |
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emphasize that their relatively large body size leads them to have feeding practices similar to those of East African mammals |
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illustrate differences between ruminants and nonruminants through the use of animals likely to be familiar to most readers |
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| 57. According to paragraph 2, which of the following herbivores has to eat large quantities of plant stems be-cause it gains relatively little energy from each given quantity of this food? |
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| 58. Paragraph 2 suggests that which of the following is one of the most important factors in determining differences in feeding preferences of East African herbivores? |
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The differences in stomach structure |
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The physical nature of vegetation in the environment |
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The availability of certain foods |
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The ability to migrate when food supplies are low |
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| 59. According to paragraph 2, all of the following are true of East African gazelles EXCEPT ................ |
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Microorganisms help them digest their food. |
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They digest their food very quickly. |
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They are unable to digest large food particles unless these are chewed down considerably. |
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They survive well even if food sup-plies are not abundant. |
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| 60. The phrase “provided that” in the passage is closest in meaning to ................ |
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| 61. The word “fastidious” in the passage is closest in meaning to ................ |
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| 62. According to paragraph 4, which of the following mammals exhibits a feeding behavior that is beneficial to the other herbivores that share the same habitat? |
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| 63. According to the passage, which of the following is true of wildebeests? |
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They are likely to choose low-quality food to eat in periods when the quantity of rainfall is low. |
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They are able to digest large food particles if the food is of a high quality. |
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They eat more stem matter than zebras do. |
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They tend to choose feeding areas in which the vegetation has been worn down. |
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| 64. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “The sequence in which they migrate correlates with their body size.” could be added to the passage. Where would the sentence best fit? |
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| 65. An introductory sentence for a brief summary of the passage is “East African herbivores, though they all live in the same environment, have a range of feeding preferences.”. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. |
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Zebras and wildebeests rarely compete for the same food resources in the same locations. |
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The different digestive systems of herbivores explain their feeding preferences. |
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Migratory habits are influenced by feeding preferences. |
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A herbivore's size and metabolic rate affect the kinds of food and the quantities of food it needs to eat. |
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The survival of East African mammals depends more than anything else on the quantity of highly nutritious fruits that they are able to find. |
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Patterns in the migratory habits of East African herbivores are hard to establish. |
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