One way to store energy is in the rotational motion of a flywheel, and some have proposed using such technology to power automobiles. One unit is based on a 5.5-kg flywheel in the shape of a hoop of radius 7.0×10−2 m that spins as fast as 60000 rpm. If the vehicle requires an average torque of 142 Nm under normal driving conditions, for how much time can it operate with the energy stored in the flywheel?