Respostas

2014-07-21T19:30:44-03:00
72km/h = 20m/s

V = Vo + at
V = 20 -2*4
V = 20 - 8
V = 12m/s

V² = Vo² + 2*a*/\S
12² = 20² +2*(-2)/\S
144 = 400 - 4/\S
-256 = -4 /\S
/\S = 256/4
/\S = 64 metros