2. Write down the formulas used in Quantity Discount Model and the four steps of using Quantity Discount model to solve an inventory management problem. Suppose that the D = 3,000, S = $36, 10.2, and Unit price P = $3. Find the optimal contract based on Quantity Discount model. Show your work. Contract Number 1 23 Discount Quantity 0 to 999 1,000 to 1,999 2,000 and over Discount (%) no discount 5 10 61