A disk rotates about its central axis starting from rest andaccelerates with constant angular acceleration. At one time it isrotating at $11\mathrm{.}0$ rev$/$s$.65$ revolutions later, its angular speed is $25\mathrm{.}0$ rev$/$s$.$

$($a$)$ Calculate the angular acceleration.

$1$ rev$/$s$2$

$($b$)$ Calculate the time required to complete the $50$ revolutions mentioned.

$2$ s

$($c$)$ Calculate the time required to attain the $9$ rev$/$s angular speed.

$3$ s

$($d$)$ Calculate the number of revolutions from rest until the timethe disk attained the $9$ rev$/$s angularspeed.

$4$ rev