How are these set up?

Dam REE LA IME MAPA TRAFFK 2:01 GARMIN Suppose Sam's Club, Operates 400 stores Sells Garmin GPS at $100 at each store Assume cost of Garmin GPS is $100 Uses continuous review policy Incurs inventory holding cost per year of 20% of product price Suppose at each Sam's Club store, for Garmin GPS, Average weekly demand is 50 units Demand at each store is independent Standard deviation of weekly demand is 10 units Lead time for Garmin to replenish cell phones is 5 weeks Garmin guarantees to deliver GPS 5 weeks after GPS are ordered Questions (10-1) What should the safety inventory (55) at each store be if Sam's Club wishes to achieve CSL of 0.90 at each store? (10-2) What is total annual holding cost of safety inventory of GPS (total of all Sam's Club stores)? Suppose now Sam's Club decides to sell Garmin GPS only online and ships all GPS from a central warehouse but wishes to increase CSL to 0.99 at the central warehouse (10-3) What is the aggregated demand at the central warehouse? (10-4) What is the standard deviation of the aggregate demand at the central warehouse? (10-5) What should the safety inventory (ss) at the central warehouse be if Sam's Club wishes to achieve CSL of 0.99 at the central warehouse? (10-6) What is the total annual holding cost of safety inventory of GPS at the central warehouse