PLEASE USE THESE NUMBERS IN SOLUTION

Question 4) Skycell, a major European cell phone manufacturer, is making production plans for the coming year. Skycell has worked with its customers (the service providers) to come up with forecasts of monthly requirements (in thousands of phones) as shown in the Table 3 below (e.g., demand in Jan. is 1,000,000 units.) Manufacturing is primarily an assembly operation, and capacity is governed by the number of people on the production line. The plant operates for 22 days a month, eight hours each day. One person can assemble a phone every 12 minutes. Workers are paid 12.5 euros per hour and a 60 percent premium for overtime. The plant currently employs 1.250 workers. Component costs for each cell phone total 30 euros. Given the rapid decline in component and finished-product prices, carrying inventory from one month to the next incurs a cost of 3.5 euros per phone per month. Skycell currently has a no-layoff policy in place. Overtime is limited to a maximum of 15 hours per month per employee. Assume that Skycell has a starting inventory of 65,000 units and wants to end the year with the same level of inventory. Assume no backlogs, no subcontracting, and no new hires. Please construct an aggregate planning model. (Constructing an aggregate planning model means defining the decision variables and writing out the objective function and the constraints for the AP optimization problem.) Table 3 - Monthly Demand for Cell Phones, in Thousands Month Demand January 1,000 February 1,100 March 1,000 April 1,200 May 1,500 June 1,600 July 1,600 August 900 September 1,100 October 800 November 1,400 December 1,700