During the operation of a 280 hp engine energy is lost to

Question

1. During the operation of a 280 hp engine, energy is lost to friction at a rate of 230 hp. What is the useful output power, and what is the efficiency of the engine?
2. A frictionless machine lifts a 210 lb load through a vertical distance of 10 ft. The input force moves through a distance of 260 ft. What is the ideal mechanical advantage of the machine? What is the magnitude of the input force?
3. A 45 kg mass is to be lifted with a rod 2 m long. If you can exert a downward force of 45 N on one end of the rod, where should you place a block of wood to act as a fulcrum?