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cenario 2: A supplier sells a popular auto part to car dealers. The weekly demand is approximately normal with the historical distribution of DN(63,25) units over a 45 -week operating year. The supplier pays $26 for each unit and sells each for $41. In addition, they estimate that the annual holding cost is 30 percent of the unit's cost (to the supplier). It costs approximately $25 to place an order (managerial and clerical costs). Assume a four-week lead time. 8. What is the distribution of the demand during lead time? 9. What is the safety stock required per order under the optimal service level