A stone is thrown straight up from the edge of a roof, $675$ feet above the ground, at a speed of $16$ feet per second.

A. Remembering that the acceleration due to gravity is $-32 \textrm{ft}/\textrm{sec}^2$, how high is the stone $2$ seconds later?

Answer: feet.

B. At what time does the stone hit the ground?

Answer: sec

C. What is the velocity of the stone when it hits the ground?

Answer: ft/sec.