Solve
-A Rock Falls from a Tower That Is $160 \mathrm { ft }$

Solve.
-A rock falls from a tower that is $160 \mathrm { ft }$ high. As it is falling, its height is given by the function $h ( t ) = 160 - 16 t ^ { 2 }$ . How many seconds will it take for the rock to hit the ground $( h = 0 )$ ?

A) $12.6 \mathrm { sec }$
B) $1600 \mathrm { sec }$
C) $10.2 \mathrm { sec }$
D) $3.2 \mathrm { sec }$