Solve the Problem $\mathrm{m} / \mathrm{sec}$ ) of a Particle Moving on The

Solve the problem.
-Suppose that the speed (in $\mathrm{m} / \mathrm{sec}$ ) 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 during what time period the speed of the particle is less than $10 \mathrm{~m} / \mathrm{sec}$ .

A) Between about $t=4$ and $t=5$ seconds
B) Between about $t=2$ and $t=4$ seconds
C) Between about $t=4$ and $t=6$ seconds
D) Between about $t=3$ and $t=5$ seconds