(a) Find the useful power output [in W] of an elevator motor that lifts a 2500 kg load a height of 30.0 m in 12.0 5:, if it also increases the speed from rest to 4.00 mfs. Note that the total mass of the counterbalanced system is 10,000 kgso that only 2500 kg is raised in height, but the full 10,000 kg is accelerated. (Enter a number.) |:|xW (b) What does it cost [in cents), if electricity is 50.0900 per kW - h? (Enter a number.) x cents