2- The Spencer Optics Company produces an inexpensive line of sunglasses. The manufacturing process consists of assembling two plastic lenses (produced by the firm's plastic molding depart- ment) into a finished frame (purchased from an outside supplier). The company is interested in using material requirements planning to schedule its operations and has asked you to prepare an example to illustrate the technique: The firm's sales manager has prepared a 10-week sales forecast for one of the more popular sunglasses (the Classic model) for your example. The forecast is 100 units per week. Spencer has customer orders of 110 units, 80 units, 50 units, and 20 units in weeks 1,2,3, and 4 respectively: The sunglasses are assembled in batches of 300 units. Presently: three such batches are scheduled: one in week 2 , one in week 5 , and one in week 8 . Complete the following time-phased record: ( Proiected on hand inv is 140 units). (15 points)