Please show work for part B

In a P system, the lead time for a box of weed-killer is three weeks and the review period is one week. Demand during the protection interval averages 215 boxes, with a standard deviation of demand during the protection interval of 50 boxes. a. What is the cycle-service level when the target inventory is set at 250 boxes? Refer to the standard normal table as needed. The cycle-service level is \%. (Enter your response rounded to two decimal places.) b. In the fall season, demand for weed-killer decreases but also becomes more highly variable. Assume that during the fall season, demand during the protection interval is expected to decrease to 170 boxes, but with a standard deviation of demand during the protection interval of 60 boxes. What would be the cycle-service level if management keeps the target inventory level set at 250 boxes? Refer to the as needed. The cycle-service level would be \%. (Enter your response rounded to two decimal places.)