What is the balance constraint for month 1 ? A. I1=P2-450 B. I1=120P1+450 c. I1=120+P1450 D. 12=120P1+450 Question 11 to Question 13 is based on this problem: The GREEN Western Electric (GWE), Inc. manufactures a variety of household appliances at its production facility. The expected demand for one of these appliances during the next 4 months is shown in the following table along with the expected production costs and the expected capacity for producing these items. GWE estimates it costs $1.50 per month for each unit of this appliance carried in inventory (estimated by averaging the beginning and ending inventory levels each month). Currently, the company has 120 units in inventory on hand for this product. To maintain a level workforce, the company wants to produce at least 400 units per month. The company also wants to maintain a safety stock of at least 50 units per month. GWE wants to determine how many of this appliance to manufacture during each of the next 4 months to meet the expected demand at the lowest possible total cost. Let Pi= number of units to produce in month i, with i=1,2,3,4. li= inventory held at the end of month i, with i=1,2,3,4. What is the total inventory cost over the next 4 months? A. 11+12+13+14 B. 1.5(11+12+13+14) C. 1.5(120+11+12+13+14) D. 1.5(60+I1+I2+I3+214) What is the balance constraint for month 4 ? A. 450=13+P4+14 B. 450=13+P415 c. 450=13+P414450=13P414