The next great land area that man hopes to control is the moon. In size it is nearly equal to the area of North and South America. However, it presents a hostile (不友好的) environment. Temperatures range +120 to -150 degrees Centigrade (摄氏). There is no air, and no water.
Today there is considerable scientific speculation (思索) about living on the moon. When man will begin life on the moon surface is still not determined. But experts believe that settlement will take place in three steps. First, there will be increasing periods of exploration with temporary shelters (临时住所). These periods will be followed by longer stays with housing under the surface of the moon and daily necessities brought by the settlers themselves from the earth. Finally, settlements that are self-supporting will be founded.
The main job of the early settlers will be to stay alive. They will have to plant crops under huge domes (圆顶屋) to produce food and oxygen and find water sources. After this is done, the settlers will have time to explore the possibilities of commercial (商业的) development and to make discoveries important to science. The characteristics of the moon that make it bad for human staying alive may make it ideal for certain kinds of manufacturing (制造业). Operations requiring a vacuum (真空) or extreme cold are examples. Therefore, industrial diamonds might be produced on the moon.
39. The area of the moon is _________.
A. about the same as that of North and South America
B. larger than that of North and South America
C. hardly equal to that of North and South America
D. far smaller than that of North and South America
40. According to this passage, the settlement of the moon ________.
will soon be realized
can be done under the moon surface
is being experimented by many scientists
D. sounds entirely impossible
41. To stay alive on the moon, the early settlers must first of all be able to ________.
A. develop commerce
B. get enough food, oxygen and water
C. make discoveries important
D. explore the possibilities of industrial development
42. Though the environment on the moon is bad for human staying alive, it is very good for ________.
A. making such things as industrial diamonds   B. all kinds of manufactured goods
C. medical operations                      D. commercial development