use least cost method (hurstic )

The maintenance manager of a facility that produces semiconductor wafers is intended to perform the maintenance capacity planning for the next four months. The table below includes the demanded maintenance workloads (in hours) in addition to the in-house regular capacity for the mentioned periods. An additional overtime capacity can be utilized such that it could contribute in work by at most 30% of the regular capacity. Also, a third-party (subcontractor) can provide the maintenance services through a contract of purchasing 120 hours-capacity in each of the four months. Regarding the resource cost, the in-house regular man-hour cost is 1 unit with a 50% increase for the overtime, while the subcontracting cost is 2 units. Backlogging increases the man-hour costs by 20% of the original costs. (a) Use the heuristic method to determine the optimum maintenance capacity plan for the workloads in the given periods. (15 Points) (b) Calculate the total cost of the resultant capacity plan in part (a). (5 Points)