2. 职称英语
  3. If the population of the Earth goes on increasing at its present rate, there

If the population of the Earth goes on increasing at its present rate, there

游客2025-03-25  26
问题     If the population of the Earth goes on increasing at its present rate, there will eventually not be enough resources left to sustain life on the planet. By the middle of the 21 century, if present trends continue, we will have used up all the oil that drives our cars, for example. Even if scientists develop new ways of feeding the human race, the crowded conditions on Earth will make it necessary for us to look for open space somewhere else. But none of the other planets in our solar system are capable of supporting life at present. One possible solution to the problem, however, has recently been suggested by an American scientist, Professor Carl Sagan.
    Sagan believes that before the Earth’s resources are completely exhausted, it will be possible to change the atmosphere of Venus and so create a new world almost as large as Earth itself. The difficulty is that Venus is much hotter than the Earth and there is only a tiny amount of water there.
    Sagan proposed that algae, organisms that can live in extremely hot or cold atmospheres and at the same time produce oxygen, should be bred in conditions similar to those on Venus. As soon as this has been done, the algae will be placed in small rockets. Spaceships will then fly to Venus and fire the rockets into the atmosphere. In a fairly short time, the algae will break down the carbon dioxide into oxygen and carbon.
    When the algae have done their works, the atmosphere will become cooler but before man can set foot on Venus, it will be necessary for the oxygen to produce rain. The surface of the planet will still be too hot for men to land on it but the rain will eventually fall and in a few years something like Earth will be reproduced on Venus.
    If the experiments are successful, life will become possible there, but it will not be pleasant at first. When they go to Venus, the first colonists will have to take plenty of water with them and get used to days and nights lasting 60 Earth-days. But there will also be some advantages. The colonists will live longer because their hearts will suffer less strain than on Earth. Apart from that, they will be exploiting a new world while those still on Earth are living in closed, uncomfortable conditions. Perhaps it will be the only way to ensure the survival of the human race. [br] The first colonists on Venus will find life difficult there because ______.
选项 A、they will suffer from heart strain
B、they will be no water there
C、the day and night will be very long
D、the rainy season lasts a few years
答案 C
解析 本题是细节题。A选项文中没有讲到。B选项错误，人们可以带水到金星。C选项讲到金星的白天和黑夜太长。文章最后一段讲，金星的白天和黑夜均有60天之久，对已经习惯12小时左右的白天和黑夜的人们来说，生活在金星上确实有困难，故C选项正确。文章中根本就没有讲到金星上有雨季，何况金星上的水非常少，故D选项是错误的。
转载请注明原文地址:http://tihaiku.com/zcyy/4011828.html
相关试题推荐
随机试题
最新回复(0)