Q$9.$ Fig. $9$ shows a four bar linkage. The drive crank $OA$ rotates anticlockwise at $500$ rpm $.$ For the position shown determine:

$($a$)$ The angular velocity of link QB

$($b$)$ The angular acceleration of link QB

$AB=0\mathrm{.}4m$

$AO=0\mathrm{.}15m$

$BQ=0\mathrm{.}25m$

$OQ=0\mathrm{.}4m$

$($a$)28\mathrm{.}3ra\frac{d}{s}($ACW$)$

$($b$)578ra\frac{d}{s^2}($CW$)$