Solve the Problem $x$ -Axis at Time $t$ Seconds $(t \geq 0)$ Is Given By

Multiple Choice

Solve the problem.
-Suppose that the speed of a particle moving on the $x$ -axis at time $t$ seconds $(t \geq 0)$ is given by:
$$V(t) =t^{3}-8 t^{2}+15 t+10$$
By sketching a graph of $C(t)$ , estimate at what time the speed of the particle is a minimum.

A) At about $t=6$ seconds
B) At about $t=4$ seconds
C) At about $t=5$ seconds
D) At about $t=3$ seconds