How does China ensure the safety of residents in rocket launch areas
A. Calculate the areas in which stages and side boosters fall
Build all the spaceports on the coast
C. Issue local warnings in advance
D. Implement evacuation orders in advance
Which rockets were launched on the coast
A. Long March 5B
B. Long March 7A
C. Long March 8
D. Long March 3B
What did Long March 7A use
A. relatively clean kerosene
B. liquid oxygen propellant
C. toxic fuel
D. oxidizer mix
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