After their rocket engines shut off, astronauts experience weightlessness in the orbiting Space Shuttle,
A. and they are accelerating because they are actually in free-fall.
B. and they are accelerating because they have constant velocity as they pass overhead.
C. but they cannot accelerate because their rocket engines are shut off.
D. but they are not accelerating, since nothing actually has weight in space.
Answer: A
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A. A·V
B. C·J
C. C/J
D. A/V
E. 
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Which of the following statements about oxidation and reduction reactions is true?
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