Jawabanmu

2014-08-13T20:04:51+07:00
K : 72km/jam
W : 20 detik
J : 6/15km = 0,4km
20 detik = 1/180 jam x 72km/jam = 6/15km

0,4km

2014-08-13T20:13:40+07:00
Jarak/waktu
72= X/3600
72 km= 72000 m
72000/3600=20 m
1 sekon = 20 m
20 sekon = 20 sekon x 20 m/s = 400 m
20 sekon = 400 meter