Respostas

2013-07-18T19:47:26-03:00
A)v^2=v0^2+2a/\s
5^2=13^2+2a*72
25=169+144a
144a=-144
a=-1
R: 1 m/s^2

b) 0^2=13^2+2*-1*s
0=169-2s
s=84,5 metros