题目内容

____ space stations have been launched in the world so far.

A. 8
B. 10
C. 12
D. 14

查看答案

搜索结果不匹配？点我反馈

更多问题

The US space shuttle has ____ main engines.

A. 3
B. 4
C. 5
D. 6

Near space vehicle includes: ____.

A. Solar-powered plane
B. Stratospheric airship
C. F-22 aircraft
D. X-51A hypersonic aircraft

Main differences between balloon and airship are ____.

A. Configuration
B. Motive power
C. Direction Control
D. Filling gases

The advantages tiltrotor aircraft have over helicopter are ____.

A. Longer flight range
B. Lower cost
C. Simpler structure
D. Higher speed