A-A+
According to the passage the most difficult t
问题详情
According to the passage, the most difficult task of firing a rocket is ______ .
A．to get the rocket into the space
B．to calculate the rocket"s velocity of escape
C．to guide the rocket after it leaves the Earth"s surface
D．to identify the gravitational fields of the Earth and the moon
参考答案
正确答案：C
解析：本题的依据句是“The problem of rocket travel is not so much concerned with getting the rocket into space as it is with guiding the rocket after it leaves the Earth's surface．”从中可知C项为正确答案。
