Determine What Signs on Values of X and Y Would $h = 750 - 16 t ^ { 2 }$

Determine what signs on values of x and y would make the statement true. Assume that x and y are not 0.
-A stone is dropped from a tower that is 750 feet high. The formula $h = 750 - 16 t ^ { 2 }$ describes the stone's height above the ground, h, in feet, t seconds after it was dropped. What is the stone's height
5 seconds after it is released?

A) 325 ft
B) 360 ft
C) 350 ft
D) 375 ft