Starting at $(w_A{)}_0=5ra\frac{d}{s},$ when $=0,s=0,$ pulley $A$ is given an angular acceleration

of $={0\mathrm{.}6}^{***}+ra\frac{d}{s^2},$ where $t$ is in seconds. The pulley has an inner hub $D$ which is

fixed to $C$ and turns with it$.$ When $t=3$ seconds, determine:

a$)$ the velocity of block B

b$)$ the distance, $s,$ the block has lifted.