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conversions préalables:
1h=3600s
1km=1000m
1h=100m
1h=60min
A) 65m/s = 65*3600 /h =234000m/h=234km/h
B)5hm/min = 5*60hm/ h = 300 hm/ h = 30km/h
C)0.18m.s-1 = 0.18*3600/s-1 = 648m/s= 0.648km/s
D)14.5m.min-1=14.5*60/1h= 870m/h=0.87km/h
1h=3600s
1km=1000m
1h=100m
1h=60min
A) 65m/s = 65*3600 /h =234000m/h=234km/h
B)5hm/min = 5*60hm/ h = 300 hm/ h = 30km/h
C)0.18m.s-1 = 0.18*3600/s-1 = 648m/s= 0.648km/s
D)14.5m.min-1=14.5*60/1h= 870m/h=0.87km/h