Twin paradox: signals sent during space voyage at 0.8c

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How would you make the first move in this type of question:

Dick and Jane are twins. Dick goes off on a space voyage at a speed of 0.8c to a star 20 light-years away, while Jane stays behind on Earth. Dick and Jane each send out a radio signal once a year while Dick is away. How many signals does Dick receive? How many does Jane receive?
 
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First off, is the star 20 light years away according to Jane's reference frame or Dick's? Secondly, after how long and according to whose frame do they count up the signals? Anyway, they should both count the same number of signals.
 
hmm... you're right~
wow! you ask some pretty good questions~