Respostas

2013-07-10T19:18:40-03:00
72km/h = 20m/s
V = Vo + a.t
0 = 20 + a.5
a = -4m/s^2
V^2 = Vo^2 + 2.a.s
0^2 = 20^2 + 2.(-4).s
s = 50m.