Tractoroo Inc. plans the monthly tractor production quantities for the next quarter. The demand during the four months is d = 140, d = 150, d3 = 160, d4 = 130. Presently, Tractoroo has an inventory of 20 tractors. During each month, Tractoroo can manufacture up to 120 tractors with regular-time labor for $1200 per unit. With overtime labor, Tractoroo can manufacture more tractors, costing $1500 per unit. A per unit inventory cost of $10 per unit is charged at the end of each month. The warehouse can fit up to 50 tractors. Develop an LP model to minimize the total production and inventory costs for the quarter. Solve your model in AMPL and report the optimal solution below. Number of tractors to manufacture with regular time labor during the first month: Number of tractors to manufacture with overtime labor during the first month: Number of tractors to manufacture with regular time labor during the second month: Number of tractors to manufacture with overtime labor during the second month: Number of tractors to manufacture with regular time labor during the third month: Number of tractors to manufacture with overtime labor during the third month: ; Number of tractors to manufacture with regular time labor during the fourth month: Number of tractors to manufacture with overtime labor during the fourth month: The optimal total production and inventory cost for the quarter: