A baseball pitcher throws a fastball that leaves his hand at a speed of 36.0m/s. The mass of the baseball is 0.145kg. Ignore air resistance. How much work has the pitcher done on the ball in throwing it?

I dunno what to use

$\displaystyle W = \frac{1}{2}m{v_{2}}^2 - \frac{1}{2}m{v_{1}}^2 $

help please

the answer is 94.0 Joules