A machine part to be machined may be made either from an alloy of aluminum or steel. There is an order for 8000 units. Steel costs P3.80 per kg. while aluminum costs P8.70 per kg. If steel is used, the steel per unit weighs 110grams, for aluminum, 30 grams. When steel is used, 50 units can be produced per hour, for aluminum, 80 units per hour with aid of tool costing P640, which will be useless after the 8,000 units are finished. The cost of the machine and the operator is P10.80 per hour How much is the ost per unit if steel is use