Solve the Problem $X$ Is $s = 4.16 t ^ { 2 } \mathrm {~m}$

Multiple Choice

Solve the problem.
-The equation for free fall at the surface of Planet $X$ is $s = 4.16 t ^ { 2 } \mathrm {~m}$ with $t$ in seconds. Assume a rock is dropped from the top of a $600 \mathrm {~m}$ cliff. Find the speed of the rock at $t = 5 \mathrm { sec }$ .

A) $42.6 \mathrm {~m} / \mathrm { sec }$
B) $41.6 \mathrm {~m} / \mathrm { sec }$
C) $19.8 \mathrm {~m} / \mathrm { sec }$
D) $20.8 \mathrm {~m} / \mathrm { sec }$