IGLE provides maintenance, repair and operations (MRO) products to its customer The Company decides the optimum customer service level based on profit maximization. According to the available data, sales response rate is 0.15% change in revenue for a 1% change in the service level (fill rate). Trading margin is $14 per sealant boxes, inventory carrying cost is 32% per year, average yearly sales amount is 5000 boxes. Cost of each sealant box is $140, demand standard deviation is 20 boxes for a week, and the lead time is 4 weeks. a) Determine the optimal customer service level for the sealant product b) What happens to the optimal customer service level if the inventory carrying cost changed to 30%