An automobile service station uses 900 cases of motor oil annually. The station operates 300 days a year. The order replenishment lead time for motor oil is 4 days with a standard deviation of 4 cases per day. The station has specified an annual service level of 97%:

1. What is the level of safety stock required assuming that demand during lead time is normally distributed?

2. If the station decides to hold only 6 six cases of motor oil as safety stock, what is the stock-out risk?