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3. v = 2 m/s = 0.002 km/(1/3600) jam = 7,2 km/jam
s = 3 km

t = s/v = 3/7,2 = 0.4 jam = 0.4 x 60 menit = 24 menit

maksimal waktu berangkat adalah
6.45 - 24 = 6.21

4. total jarak = 33 + 60 + 31 = 124 km
total waktu = 0.5 jam + 1 jam + 0.5 jam = 2 jam
v = total jarak/total waktu
v = 124 km / 2 jam = 62 km/jam

5. vo = 36 km/ jam = 36000km/(3600s) = 10 m/s
a = -2 m/s²

v = vo + at
0 = 10 - 2t
2t = 10
t = 5 s