Given the following information set up the problem in a transportation table and solve for the minimum-cost plan:

PERIOD123Demand550700750CapacityRegular500500440Overtime505050Subcontract120120100Beginning inventory100CostsRegular time$60 per unitOvertime$80 per unitSubcontract$90 per unitInventory carrying cost$1 per unit per monthBack-order cost$3 per unit per month

Suppose that an inventory carrying cost is increased$2 per unit per period. What will the additional cost of the optimal plan be?(Omit the "$" sign in your response.)