At t $=$ O a grinding wheel has an angular velocity of

$24\mathrm{.}0$ rad$/$s$.$ It has a constant angular acceleration of $30\mathrm{.}0$ rad$/$s$2$

until a circuit breaker trips at t $2\mathrm{.}00$ s$.$ From then on$,$ it turns

through $432$ rad as it coasts to a stop at constant angular accel$-$

eration. $($a$)$ Through what total angle did the wheel turn between

t $0$ and the time it stopped? $($b$)$ At what time did it stop? $($c$)$ What

was its acceleration as it slowed down?