marwick piano incorporated purchases from a large manufacturer for an average cost of 2450 per unit and sells them to retail customers for an average cost of 3125 each.the company 's selling and administrative costs for a typical month are presented below

selling: Advertising 700 per month sales salaries and commission 950 per month,plus 8% of sales delivery of piano to customers 30 per piano sold utilities 350 per month depreciation of sales facilities 800 Administrative : executive salaries 2500 per month insurance 400 per month clerical 1000 per month ,plus $20 per piano sold depreciation of office equipment $300 per month