(9) [6 points] Consider a flywheel that is a solid cylindrical disk 0.2 meters in radius with a mass of 40 kg. The flywheel turns at 700 rpm until acceleration is applied by an external torque; in 6 seconds the flywheel turns at 2500 rpm. (a) What magnitude of torque was applied, assuming constant angular acceleration? (b) How much energy was stored in the flywheel when it was turning at top speed? Now consider recovering the energy stored in the flywheel to do useful work. Assume energy is extracted with 100% efficiency in returning the flywheel to 700 rpm. (c) How much energy is recovered? (d) Calculate the equivalent height one would have to lift a 40 kg mass to recover the same amount of energy as gravitational potential energy (g = 9.81 m/sz)