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Jerusalem Medical Ltd., an Israeli producer of portable kidney dialysis units and other medical products, develops a 4-month aggregate plan. Demand and capacity (in units) are forecast as follows: Month 1 Month 2 Month 3 Month 4 265 280 Capacity Source Labor Regular time Overtime Subcontract Demand 28 26 300 24 245 15 14 260 17 17 18 316 310 301 The cost of producing each dialysis unit is $875 on regular time, $1,310 on overtime, and $1,600 on a subcontract. Inventory carrying cost is $100 per unit per month. There is to be no beginning or ending inventory in stock and backorders are not permitted. Minimizing cost using the transportation method, the optimal cost is $ (enter your response as a whole number)