Respostas

2014-08-11T19:22:37-03:00
 \frac{12:12}{3600:12}= \frac{1}{300}h

0=73+a* \frac{1}{300}

a= \frac{-73}{1/300}= \frac{-73}{1}* \frac{300}{1}= \frac{-21900}{1}=-21900km/h^2

Se quiser em m/s² divida por 12960,

 \frac{-21900}{12960}=-1,69m/s^2