Scientists have always wanted to know more about the universe. Years ago they knew many things about the moon. They knew how big

admin2013-05-15  45

问题     Scientists have always wanted to know more about the universe. Years ago they knew many things about the moon. They knew how big it was and how far away from the earth. But they wanted to know more about it. They thought the best way was to send men to the moon. The moon is about 384, 000 kilometers away from the earth. A plane cannot fly to the moon because the air reaches only 240 kilometers away from the earth. But something can fly even when there is no air. That is a rocket.
    How does a rocket fly? There is gas in the rocket. When the gas is made very hot inside the rocket, it will rush out of the end of the rocket, so it can make the rocket fly up into the sky. Rockets can fly out into space. Rockets with men in them have been to the moon. Several rockets without men in them have flown to another planet much farther away than the moon. One day rockets may be able to go to any place in space.  
A plane cannot fly to the moon because _____.

选项 A、there is no air above 240 kilometers away from the earth
B、there is no gas in the plane
C、the plane is not strong enough
D、the plane must be driven by a man

答案A

解析 事实细节题。由第一段倒教第三句“A plane cannot fly to the moon because the air reaches only 240kilometers away from the earth.”可知,飞机不能飞往月球是因为离地球240千米之外没有大气。故选A。
转载请注明原文地址:https://jikaoti.com/ti/e1tfFFFM
0

最新回复(0)