阅读理解。
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 it was
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 where 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 rocket, pushing the rocket up into the sky. Rockets can fly far 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.
1. What did scientists know about the moon years ago? [ ]
A. The size of the moon.
B. The distance between the earth and the moon.
C. Life on the moon.
D. Both A and B.
2. A plane cannot fly to the moon because _____. [ ]
A. its engine is not powerful enough
B. it cannot fly so high
C. there is no air on the moon
D. the moon is too far away from the earth
3. A rocket is driven by _____. [ ]
A. electricity
B. hot gas inside it
C. atomic energy
D. energy from sunlight
4. Which of the following is NOT true? [ ]
A. Rockets can fly into outer space.
B. Rockets have flown to most of the planets so far.
C. Rockets with men cost more than rockets without men.
D. Rockets without men appeared earlier than rockets with men.
5. Choose the best title for this passage? [ ]
A. The Moon and Planets.
B. Flying to the Moon.
C. How Does a Rocket Fly?
D. Rockets in the Universe.
．造成这一现象的原因不可能是