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Jose Martinez of El Paso has developed a polished stainless steel tortilla machine that makes it a "showpiece" for display in Mexican restaurants. His forecast of capacity and demand follows: 1 150 2 160 Month 3 140 4 210 5 230 Demand Capacity Regular time Overtime 150 20 140 30 160 20 150 10 150 20 Subcontracting 100 units available over the 5-month penod Beginning inventory 0 units Ending inventory required 20 units Costs Regular-time cost per unit $80 Overtime cost per unit $115 Subcontract cost per unit $128 Inventory holding cost per unit per month $4 Assume that backorders are not permitted. Using the transportation method, the total cost of the optimal plan is $(enter your response as a whole number)