Respostas

2013-08-30T00:25:21-03:00
Nano segundo = 10^-9

1km = 1000 m = 10³ m

v = 3.10^8

t =  \frac{S}{V} =  \frac{10^{3} }{3.10^{8} } = 0,333.10^{-5}= 3,33.10^{-4} .10^{-9} = 3,33.10^{-13}  nano segundos
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