Please help. I'm so confused. It's about Fixed-Time Period Model. Thanks in advance.

FIXED-TIME PERIOD MODEL 1. A drug store orders its antibiotics every two weeks when a salesperson visits from one of the pharmaceutical companies. Amoxycillin is one of its most prescribed antibiotics, with an average daily demand of 1,500 capsules. The standard deviation of daily demand was derived by examining prescriptions filled over the last three months and was found to be 500 capsules. It takes nine days for the order to arrive. The drug store manager has set a service level of 99 per cent. The salesperson has just arrived, and there are currently 25,000 capsules in stock. a) How much additional stock must be carried to minimize the risk of stockout? b) How many capsules of Amoxycillin should be ordered if lot size per order is 100 capsules? 2. The weekly demand for a product is 770 units. The standard deviation of daily demand is 10 units. The firm reviews its inventory every 28 days. Each order for the product arrives 9 days after placement. At the time of review, there are 10 units backorder. If 95 percent of all demand is to be satisfied from items in stock: a) How many units should be the safety stock? b) What's the product's inventory status? c) How many units should be ordered for this period