9. An item in the product line for the food company discussed in question 8 has the following characteristics: Sales response rate = 0.15% change in revenue for a 1% change in the service level Trading margin = 0.75 per case Annual sales through the warehouse = 80,000 cases Annual carrying cost = 25% Standard product cost = $10.00 Demand standard deviation = 500 cases per 1 week lead time Lead time = 1 week Find the optimum service level for this item