must use excel & show formulas #7

7) A manager needs to buy raw materials for their production process. For a particular raw material, the manager uses 40,000 units each year. The supplier has quoted a price of $4.50 per unit for an order size of 999 units or less, a price of $4 per unit for orders of 1000 to 4999 units, and a price of $3.75 per unit for an order of 5,000 or more units. There is an annual holding cost of 50 percent of the price of the unit for this inventory. Assume ordering cost is $20/order. What is the order quantity if the objective is to minimize total annual costs of holding ordering, and purchasing (be sure to identity total costs of 3 options)? (20 pts)