A local firm manufactures children’s toys. The projected demand over the next four months for one particular model of toy robot is Month Workdays Forecasted Demand (in aggregate units)
July 23 3,825
August 16 7,245
September 20 2,770
October 22 4,440

Assume that a normal workday is eight hours. Hiring costs are $350 per worker and firing costs (including severance pay) are $850 per worker. Holding costs are $4.00 per aggregate unit held per month. Assume that it requires an average of 1 hour and 40 minutes for one worker to assemble one toy. Shortages are not permitted. Assume that the ending inventory for June was 600 of these toys and the manager wishes to have at least 800 units on hand at the end of October. Assume that the current workforce level is 35 workers.

Required:
a. Find the minimum constant workforce plan for the four months and the total hiring, firing, and holding costs of that plan.
b. Determine the plan that changes the workforce level each month to most closely match the demand and the cost of that plan.