b) The Elite Cafe serves purified bottles of "Wata" to its customers. The daily demand for Wata is normally distributed, with an average demand of 18 bottles and a standard deviation of 4 bottles. The lead time to receive an order of Wata from the local supplier is 3 days. Determine the safety stock and reorder point if the Cafe wants to maintain : i) 90% service level ( 5 Marks) ii) 95% service level (5Marks)