QUESTION 4 a. From the following figures find the gross profit margin and the net profit margin: Gross Sales $650,000 Sales returns 50,000 Opening stock 25,000 Closing stock 30,000 Purchases 410.000 Office and Admin expenses 50.000 Selling and distribution expenses 40,000 b. If the firm has total assets of $950,000 and total shareholders' equity of $440,000, find the return on assets and return on equity