Jawabanmu

2014-03-28T09:18:44+07:00
Diket: v = 4 m/s
s1 = 5 km => 5000 m; s2 = 400 m

Ditanya: t =?
jawab: t = s/v => s1/v => 5000/4 = 1250 detik
s2/v = 400/4 = 100 detik