题目内容

The passage suggests which of the following about air pollution？

A. Further attempts to reduce emission from gasoline-fueled vehicles will not help lower urban air-pollution level.
B. Attempts to reduce the pollutants that an individual gasoline-fueled vehicle emits have been largely unsuccessful.
C. Few serious attempts have been made to reduce the amount of pollutants emitted by gasoline-fueled vehicles.
D. Pollutants emitted by gasoline-fueled vehicles are not the most critical source of urban air pollution.

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What contribution does the author feel people must make now？

A. Search for new energy sources.
Ban motor transportation.
C. Accept a new life style.
D. Adopt a new form. of government.

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The situation has not changed much since the Dark Ages. Truth is still sought because it has value, and the scientific method remains the most systematic way of pursuing it. The method starts with a problem. Once the problem is well defined, information that might have an effect on it is gathered. The information is sorted and analyzed, and that which is useful is kept—to be used as a basis for general principles. In the social sciences, the principles are often used to help formulate policies. The policies ultimately are aimed at removing the problem and improving people's lives.
In economics (and in other social sciences), the pursuit of truth is slowed because human behavior. cannot be subjected to the kinds of controlled experiments that are possible with white rats and guinea pigs. The economist must follow the steps in a search for new truths about economic behavior, but following them is frustrating and often leads up blind alleys. Nevertheless, problems, facts, principles, and policies must be considered in a systematic way.
What can we infer from the fact that the world was perceived as flat？

A. Most people during the Dark Ages were illiterate.
B. People during the Dark Ages were lacking in social knowledge.
C. People today were more knowledgeable than those during the Dark Ages.
D. People's cognition of the world was related to the scientific development.

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It can be inferred from the passage that a vehicle specifically designed to use methanol for fuel would______.

A. be somewhat lighter in total body weight than a conventional vehicle fueled with gasoline
B. have a larger and more powerful engine than a conventional vehicle fueled with gasoline
C. average more miles per gallon than a "gasoline alone" vehicle fueled with methanol
D. have a larger and heavier fuel tank than a "gasoline alone" vehicle fueled with methanol

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The author wrote the passage in order to

A. call for cooperation of the whole world.
B. inform. the readers of the fact that we are facing energy crisis.
C. recommend a new life style.
D. call for devotion to the nature and our future generation.

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