The Hardware Warehouse is evaluating the safety stock policy for all its items, as identified by theSKU code. For SKU M4389, the company always order 80 units each time an order is placed. Thedaily demand is constant, at 5 units per day; the lead time is normally distributed, with a mean of 3days and a standard deviation of 2. Holding cost is $3 per unit per year. A 95% service level is to be maintained.

Q: How much safety stock should be carried, and what should be the reorder point?

I don't know how Z that should I find?