Jawabanmu

2014-09-09T09:25:34+07:00
DiK
ket 
1 km = 1000 m
1 jam = 60 menit = 3600 sekon
1 menit = 60 sekon

maka
V = 90 km/jam = 25 m/s
t = 20 menit     = 1200 s
s = ?


s = V.t
s = 25 .1200
s = 30000 m = 30 km


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