Highlife corporation has the following information: average demand = 30 units per day average lead time = 40 days item unit cost = $45 for orders of less than 400 units item unit cost = $40 for orders of 400 units or more ordering cost = $50 inventory carrying cost = 15 percent the business year is 300 days. standard deviation of demand during lead time = 90 desired service level = 95 percent what is the safety stock that highlife corporation should carry for its desired service level of 95 percent? 1.28 standard deviations cover 90 percent 1.65 standard deviations cover 95 percent 1.96 standard deviations cover 97.5 percent