A car is designed to get its energy from a rotating flywheel with a radius of 2.0 m and a mass of 600 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up to 5000 rev/min. (a) Find the kinetic energy stored in the flywheel. (b) if the flywheel is to supply energy to the car as a 10.0 hp motor would, find the length of time the car could run before the flywheel would have to be brough back up to speed.