The power source of electric power device mainly comes from: ____.
A. Solar cell
Battery
C. Wind energy battery
D. Fuel cell
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The advantages of rocket engine compared with aeroengine include: ____.
A. The thrust is not affected by the flight attitude
B. Larger thrust
C. High thrust-to-weight ratio
D. Self-contained combustion agent
Non-chemical rocket engines are generally accelerated to emit: ____.
A. Hydrogen
B. Helium
C. Argon
D. Xenon
The propellant feeding system of liquid rocket engine includes: ____.
A. Vacuum system
B. Pressure-feed system
C. Gravity transporting system
D. Pump-feed system
About "Minuteman III", which of following are true? ____.
A. It is intercontinental missile
B. It is ballistic missile
C. The third stage adopts solid rocket engine
D. It has a firing range of more than 12,000 kilometers
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