Question 1 10 marks A manager is attempting to put together an aggregate plan for the coming nine months. She has obtained a forecast of expected demand for the planning horizon. The plan must deal with highly seasonal demand; demand is relatively high in periods 3 and 4 and again in period 8, as can be seen from the following forecasts: Period 2 3 5 6 9 Total Forecast 190 230 260 280 210 170 160 260 180 1,940 The department now has full-time employees, each of whom can produce 10 units of output per period at a cost of RM6 per unit. Inventory carrying cost is RM5 per unit per period, and backlog cost is RM10 per unit per period. Required: Formulate and evaluate the following plans: i) Plan A: Use overtime (RM9 per unit, maximum output 25 units per period). Use inventory variation and minimize backlogs. The ending inventory in period 9 should be zero, and the limit on backlogs is 60 units per period. Assume 20 full-time workers. ii) Plan B: Use some combination of laying off (RM100 per worker), subcontracting (RM8 per unit, maximum of 20 units per period, must use for three consecutive periods), and overtime (RM9 per unit, maximum of 25 per period, maximum of 60 for the planning horizon). Assume you start with 21 workers. (10 marks)