A motorcyclist is traveling along a road. He sees another cyclist ahead and starts to accelerate for 5 seconds to pass him. The angular acceleration of the wheels is 6 rad/s^2, and just after passing, the angular velocity of the wheels is 75 rad/s.
a) What is the angular velocity of the wheels when he starts to accelerate?
b) What is the angular displacement of the wheels during this 5 second time?