Respostas

2014-07-22T15:02:11-03:00
ΔS=300-240
ΔS=60km
Vm=ΔS/ΔT
80=60/ΔT
ΔT=60/80
ΔT=6/8
ΔT=3/4 h ou 45 minutos

Logo,
7h 30min+ 45min= 8h 15 min