SUSTAIN is a reputed manufacturer of `green' fiberglass insulation,containing recycled glass, used for insulating buildings (homes, schools etc.) in the Mid-West region. Using recycled glass reduces the energy requirements during manufacturing significantly.The marketing department has forecasted the annual demand of insulation at 2,400 tons. Currently, SUSTAIN uses 60% used glass (by weight) in its insulation and organizes recycling drives to collect used glass bottles. Assuming holding cost is $20 per ton and fixed cost of hauling scrap glass is $100. Using the EOQ model answer the following questions:
(a) Draw the saw tooth inventory profile. What does the cycle time correspond to in this example?
(b) How much used glass (in tons) would SUSTAIN need to collect in every drive to meet demand?
(c) How frequently would SUSTAIN need to organize collection drives to minimize annual inventory costs?