please answer only if you are 100% correct.

A local merchandise store places order every 4 weeks. The weekly demand for a product it orders periodically has been observed to have followed the normal distribution with a mean of 50 units and standard deviation of 10 units. The lead time to receive the order once it is placed is 1 week. Lead time is assumed not having any uncertainty. The store would like to maintain a service level of 95 percent. What should be the safety stock? Round-up to the nearest integer O a None is correct Ob. 35 Oc37 Od 40 e 35 Al-Jareer book store uses 2-week periodic review period for its books inventory. For a particular book, the weekly demand during the 2-week review period is assumed to be normally distributed with a mean of 20 units (books) and the standard deviation of 5 units. Whereas, during the lead time period of 4 days, the demand also behaves normally with mean 5 unit and a standard deviation of 3 units respectively. Given the store only permits 1 percent stockout situation, what should be the safety stock? Round-up to the nearest integer O a 18 Ob. 10 Oc 7 d. None is correct O.e. 13