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TEXT E Cars account for half the oil consumed in the U.S., about half the urban pollution and one fourth the greenhouse gases. They take a similar toll of resources in other industrial nations and in the cities of the developing world. As vehicle use continues to increase in the coming decade, the U.S. and other countries will have to deal with these issues or else face unacceptable economic, health-related and political costs. It is un likely that oil prices will remain at their current low level or that other nations will accept a large and growing U.S. contribution to global climatic change. Policymakers and industry have four options: reduce vehicle use, increase the efficiency and reduce the emissions of conventional gasoline powered vehicles, switch to less harmful fuels, or find less polluting driving systems. The last of these-in particular the introduction of vehicles powered by electricity-is ultimately the only sustainable option. The other alternatives are attractive in theory but in practice are either impractical or offer only marginal improvements. For example, reduced vehicle use could solve traffic problems and a host of social and environmental problems, but evidence from around the world suggests that it is very difficult to make people give up their cars to any significant extent. In the U .S., mass-transit ridership and carpooling have declined since World War Il . Even in western Europe, with fuel prices averaging more than $ 1 a liter (about $ 4 a gallon) and with easily accessible mass transit and dense populations, cars still account for 80 percent of all passenger travel. Improved energy efficiency is also appealing, but automotive fuel economy has barely made any progress in 10 years. Alternative fuels such as natural gas, burned in internal-combustion engines, could be introduced at relatively low cost, but they would lead to only marginal reductions in pollution and greenhouse emissions (especially because oil com panics are already spending billions of dollars every year to develop less polluting types of gasoline) . The U.S. has to deal with the problems arising from vehicle use he cause______.
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TEXT B When imaginative men turn their eyes towards space and wonder whether life exists in any part of it, they may cheer themselves by remembering that life need not resemble closely the life that exists on Earth. Mars looks like the only planet where life like ours could exist, and even this is doubtful. But there may be other kinds of life based on other kinds of chemistry, and they may multiply on Venus or Jupiter. At least we cannot prove at present that they do not. Even more interesting is the possibility that life on their planets may be in a more advanced stage of evolution. Present-day man is in a peculiar and probably temporary stage. His individual units retain a strong sense of personality. They are, in fact, still capable under favorable circumstances of leading individual lives. But man’s societies are already sufficiently developed to have enormously more power and effectivenessthan the individuals have. It is not likely that this transitional situation will continue very long on the evolutionary time scale. Fifty thousand year’s from now man’s societies may have become so close-knit that the individuals retain no sense of separate personality. Then little distinction will remain between the organic parts of the multiple organism and the inorganic parts (machines) that have been constructed by it. A million years further on man and his machines may have merged as closely as the muscles of the human body and nerve cells that set them in motion. The explorers of space should be prepared for some’ such situation. If they arrive on a foreign planet that has reached an advanced stage (and this is by no means impossible), they may find it being inhabited by a single large organism composed of many closely cooperating units. The units may be "secondary"-machines created millions of years ago by a previous form of life and given the will and ability to survive and reproduce. They may be built entirely of metals and other durable materials. If this is the case, they may be much more tolerant of their environment, multiplying under conditions that would destroy immediately any organism made of carbon compounds and dependent on the familiar car bon cycle. Such creatures might be relics of a past age, many millions of years ago, when their planet was favorable to the origin of life, or they might be immigrants from a favored planet. According to this passage, some people believe that eventually______.
TEXT D Imagine eating everything delicious you want-with none of the fat. That would be great, wouldn’t it New "fake fat" products appeared on store shelve in the United States recently, but not everyone is happy about it. Makers of the products, which contain a compound called olestra, say food manufacturers can now eliminate fat from certain foods. Critics, however, say the new. eliminate can rob the body of essential vitamins and nutrients and can also cause unpleasant side effects in some people. So it’s up to decide whether the new fat-free products taste good enough to keep eating. Chemists discovered olestra in tile late 1960s, when they were searching for a fat that could be digested by infants more easily. Instead of finding the desired Fat, the researchers created a fat that can’t be digested at all. Normally, special chemicals in the intestines "grab" molecules of regular fat and break them down so they can be used by the body. Amolecule of regular fat is made up of three molecules of substances called fatty acids. The fatty acids are absorbed by the intestines and bring with them the essential vitamins A, D, E, and K. When fat molecules are present in the intestines with any of those vitamins, the vitamins attach to tbe molecules and are carried into the bloodstream. Olestra, which is made from six to eight molecules of fatty acids, is too large for the intestines to absorb. It just slides through the intestines without being broken down. Manufacturers say it’s that ability to slide unchanged through the intestines that makes olestra so valuable as a fat substitute. It provides consumers with the taste of regular fat without any bad effects on the body. But critics say olestra can prevent vitamins A, D, E, and K from being absorbed. It can also prevent the absorption of carotenoids, compounds that may reduce the risk of cancer, heart disease, etc. Manufacturers are adding vitamins A, D, E, and K as well as carotenoids to their products now. Even so, some nutritionists are still concerned that people might eat unlimited amounts of food made with the fat substitute without worrying about how many calories they are consuming. The result of the search for an easily digestible fat turned out to be______.
TEXT B When imaginative men turn their eyes towards space and wonder whether life exists in any part of it, they may cheer themselves by remembering that life need not resemble closely the life that exists on Earth. Mars looks like the only planet where life like ours could exist, and even this is doubtful. But there may be other kinds of life based on other kinds of chemistry, and they may multiply on Venus or Jupiter. At least we cannot prove at present that they do not. Even more interesting is the possibility that life on their planets may be in a more advanced stage of evolution. Present-day man is in a peculiar and probably temporary stage. His individual units retain a strong sense of personality. They are, in fact, still capable under favorable circumstances of leading individual lives. But man’s societies are already sufficiently developed to have enormously more power and effectivenessthan the individuals have. It is not likely that this transitional situation will continue very long on the evolutionary time scale. Fifty thousand year’s from now man’s societies may have become so close-knit that the individuals retain no sense of separate personality. Then little distinction will remain between the organic parts of the multiple organism and the inorganic parts (machines) that have been constructed by it. A million years further on man and his machines may have merged as closely as the muscles of the human body and nerve cells that set them in motion. The explorers of space should be prepared for some’ such situation. If they arrive on a foreign planet that has reached an advanced stage (and this is by no means impossible), they may find it being inhabited by a single large organism composed of many closely cooperating units. The units may be "secondary"-machines created millions of years ago by a previous form of life and given the will and ability to survive and reproduce. They may be built entirely of metals and other durable materials. If this is the case, they may be much more tolerant of their environment, multiplying under conditions that would destroy immediately any organism made of carbon compounds and dependent on the familiar car bon cycle. Such creatures might be relics of a past age, many millions of years ago, when their planet was favorable to the origin of life, or they might be immigrants from a favored planet. Humans on Earth today are characterized by______.
Questions 7 and 8 are based on the following news. At the end of the news item, you will be given 20 seconds to answer the questions. Now listen to the news. According to the news item, ______was the main driving force for the high rate of industrial output in the second quarter.
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