Marwick's Pianos, Inc., purchases pianos from a large manufacturer and sells them at the retail level. The pianos cost, on the average, $1,511 each from the manufacturer. Marwick's Pianos, Inc., sells the pianos to its customers at an average price of $3,000 each. The selling and administrative costs that the company incurs in a typical month are presented below: Costs Selling Cost Formula Advertising Sales salaries and commissions Delivery of pianos to customers Utilities Depreciation of sales facilities $935 per month $4,800 per month, plus 5% of sales $57 per piano sold $662 per month $5,066 per month Administrative: Executive salaries Insurance Clerical Depreciation of office equipment $13,478 per month $704 per month $2,491 per month, plus $41 per piano sold $870 per month During August, Marwick's Pianos, Inc., sold and delivered 57 pianos