One billion people in the world are short of water. How can this problem be solved? Some suggestions have been to desalinate oce

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问题     One billion people in the world are short of water. How can this problem be solved? Some suggestions have been to desalinate ocean water or to build enormous water pipelines from areas where water is abundant.(Suggestions such as these prove extremely expensive when they are actually used.)One possibility that scientists are considering is pulling icebergs from either the North Pole or the South Pole to parts of the world with a water shortage. Although many questions must be answered before such a project could be tried, moving icebergs seems a reasonable possibility in the future.
    Engineers, mathematicians, and glaciologists from a dozen countries have been considering the iceberg as a future source of water. Saudi Arabia is particularly interested in this project because it has a great water shortage. Scientists estimate that it would take 128 days to transport a large iceberg(about 1/2 square mile)to Saudi Arabia. Yet the iceberg would be completely melted by the 104th day. Therefore, insulation would be essential, but how to insulate the iceberg remains an unsolved problem.
    The problems in transporting an iceberg are numerous. The first problem is choosing the iceberg to pull. The icebergs that form in the North Pole are quite difficult to handle because of their shape. Only a small portion extends above the water — most of the iceberg is below the surface, which would make it difficult to pull. South Pole icebergs, on the other hand, are flat and float like table tops. Thus they would be much easier to move.
    How can a 200-million-ton iceberg be moved? No ship is strong enough to pull such enormous weight through the water. Perhaps several ships could be used. Attaching ropes to an iceberg this size is also an enormous problem. Engineers think that large nails or long metal rods could be driven into the ice. What would happen if the iceberg splits into several pieces during the pulling? Even if an iceberg with very few cracks were chosen, how could it be pulled through stormy waters? Furthermore, once the iceberg reached its destination, very few ports would be deep enough to store it.
    All of these problems must be solved before icebergs can become a reasonable source of water. Yet scientists estimate that it will be possible to transport them in the near future. Each year, enough icebergs form to supply the whole world with fresh water for a full year. In addition, icebergs are free and nonpolluting. As a solution to the world’s water problems, icebergs may be a workable possibility.
Which of the following is NOT a problem in transporting icebergs?

选项 A、The size of the iceberg.
B、The shape of the iceberg.
C、The temperature of air and water.
D、The salt in the iceberg.

答案D

解析 事实细节题。第二段讲到了运输冰山过程中的隔热问题,即C;第三段讲到由于冰山的不同形状造成运输困难,即B;第四段讲到运输过程中冰山的大小也是个问题,即A,故选D。
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