## Fundamentals of Physics Extended (10th Edition)

$a=-24\frac{m}{s^2}$
We have to find acceleration when $v=0$ (not including when $t=0$). From part(e), we have $t=4s$ Acceleration is given as: $a=24-12t$ We plug in the value $t=4$ to obtain: $a=24-12(4)$ $a=-24\frac{m}{s^2}$