Answers

2016-02-15T18:29:47+05:30
Yes, any type if clock is enough, but a stopwatch gives us a more accurate reading I.e in seconds. So we use stopwatch.
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2016-02-15T18:30:37+05:30
Stopwatch keeps the track of time taken by an athlete  in an particular game in a very accurate way
but other watches do not 
but any type of clock is ok
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