a hospital's biomedical repair shop uses a 4-week periodic system to maintain the inventory on the blood pressure cuff repair parts. they use an average 40 adult arm cuffs with a standard deviation of 6 cuffs every 4 weeks. cuffs aren't the most critical item they carry, but the manager would like to avoid the embarrassment of a stockout at least 95% of the time. what should their restocking level be? (hint: 95% service level is associated with z value equals to 1.65)