AGGREGATE PLANNING. I need help to solve this problem in excel file.

Question 2: A manager is apptempting to put together an aggregate plan for the cmoing year. She has obtained a forecast pf expected demand for the planning horizon. The plan must deal with highly seasonal demand as can be seen from the following forecasts: 1 2 3 4 5 6 7 8 9 Period Forecastes demand (units) 190 230 260 280 210 170 160 260 180 The department has 20 full-time operators, each of whom can produce 10 units of output per period. Starting inventory is 40 units and 20% is safety stock. Cost Inventory holding cost $5 per unit Hiring and tranning cost $300 per worker Layoff cost $500 per worker Cost of subcontracting $30 per unit Regular-time cost $4 per hour Overtime cost $6 per hour Blacklog cost $10 per unit A. Determine the total cost of the plan for strategies as belows: a. Hiring and firing, no overtime b. Constant workforce c. Subcontracting B. Which startegy provided the lowest cost