Answers

2016-03-07T13:08:36+05:30
They communicate by radios in their suits.
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2016-03-07T13:14:16+05:30
The space is actually a vacuum where there is no air.  The sound travels through a medium every time may it be a solid, liquid or air/gas. On the surface of the moon there is no medium for the sound to travel. Hence " they use radio which produces the radio active waves " to communicate on the surface of the moon.
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