On Venus there is a lot of

A． water

B． carbon dioxide

C． carbon monoxide

D． oxygen

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参考答案

答案解析

【答案】B。解析：由第二段的最后一句话中的“there is only a tiny amount of water there(Venus)”得知，A选项错误。第三段结尾说明，藻类通过火箭运往金星，然后“In a fairly short time．the algae will break down the carbon dioxide into oxygen and carbon”，说明金星上有大量的二氧化碳。C和D选项错误。故选B。

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1 Algae are plants that can

A． live in very hot temperatures

B． live in very cold temperatures

C． manufacture oxygen

D． all of the above

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2 Man can eventually land on Venus only when

A． the algae have done their work

B． the atmosphere becomes cooler

C． there is oxygen

D． it rains there

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3 根据以下材料，回答题
In the late 1960s, many people in North America turned their attention to environmental problems, and new steel-and-glass skyscrapers were widely criticized. Ecologists pointed out that a cluster of tall buildings in a city often transportation and parking lot capacities.
Skyscrapers are also lavish consumers, and wasters of electric power. In one recent year, the addition of 17 million square feet of skyscraper office space in New York City raised the peak daily
demand for electricity by 120 000 kilowatts--enough to supply the entire city of Albany, New York, for a day.
Glass-walled skyscrapers can be especially wasteful. The heat loss (or gain) through a wall ofhalf-inch plate glass is more than ten times that through a typical masonry wall filled with insula-tion board. To lessen the strain on heating and air-conditioning equipment, builders of skyscrapers have begun to use double-glazed panels of glass, and reflective glasses coated with silver or gold mirror films that reduce glare as well as heat gain. However, mirror-walled skyscrapers raise the temperature of the surrounding air and affect neighboring buildings.
Skyscrapers put a severe strain on a city's sanitation facilities, too. If fully occupied, the two World Trade Center towers in New York City would alone generate 2.25 million gallons of raw sewage
each year-as much as a city the size of Stamford, Connecticut, which has a population of more than 109 000.
Skyscrapers also interfere with television reception, block bird flyways, and obstruct air traf-fic. In Boston in the late 1960s, some people even feared that shadows from skyscrapers would kill the grass on Boston Common.
Still, people continue to build skyscrapers for all the'reasons that they have always built them-personal ambition, civic pride, and the desire of owners to have the largest possible amount of rentable space.
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A． discuss the advantages and disadvantages of skyscrapers

B． compare skyscrapers with other modern structures

C． describe skyscrapers and their effect on the environment

D． illustrate various architectural

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