ABC manufacturing company has orders for three similar castings used in aircraft engine fuel pumps. The company has three N/C machines that can machine the castings at the same production rate. However, because of varying defect / rejection rates, the unit costs of the products vary depending on the machine utilized. The following table gives the capacities by machine and the unit costs, by product, by machine for the parts, and the demand for each type casting.

Develop the minimum cost production schedule for making the required number of parts. (Which) machines make which parts?