Jimmy's Delicatessen sells large tins of Tom Tucker's Toffee. The deli uses a periodic review system, checking inventory levels every 10 days, at which time an order is placed for more tins. Order lead time is 3 days. Average daily demand is 7 tins, so average demand during the re order period and order lead time (13 days) is 91 tins. The standard deviation of demand during this same 13-day period is 17 tins. Calculate the restocking level. Assume that the desired service level is 90%.