A ceiling fan is set on high but is turned OFF. According to the owner$$s manual, when it is switched ON$,$ the motor provides enough torques to give the blades a constant angular acceleration until they are rotating at $286\mathrm{.}5$ RPM$,$ and it takes $6\mathrm{.}000$ seconds for the fan to reach this angular speed.

 

a$.$ Calculate the fan blades$$ angular acceleration to four significant figures.  

b$.$ What angle does each blade rotate through while the fan is coming up to its high speed?