Kwok is standing on top of a $160$-foot tall building and throws a tennis ball straight up with an initial velocity of $24$ ft/sec.

1. How far up does the tennis ball go before it turns around and starts to come down?

   Hint (a):

   The tennis ball turns around when $v\left(t\right) = 0$.

2. How fast is it going when it hits the ground below?

   Hint (b):

   Evaluate $v\left(\text{time of impact}\right)$. Let $h\left(t\right) = 0$ to find the time of impact.