Crane Medical manufactures hospital beds and other institutional furniture. The company's comparative balance sheet and income statement for 2019 and 2020 follow. Crane Medical Comparative Balance Sheet As of December 31 2020 2019 Assets Current assets Cash $366,000 $417,400 Accounts receivable, net 1,080,000 776,450 Inventory 736,000 681,100 Other current assets 381,350 247,050 Total current assets 2,563,350 2,122,000 Property, plant, & equipment, net 8,666,440 8,440,015 Total assets $11,229,790 $10,562,015 Liabilities and Stockholders' Equity Current liabilities $3,169,000 $2,846,000 Long-term deht 3702 600 3892 700 Long-term debt 3,702,600 3,892,700 Total liabilities 6,871,600 6,738,700 Preferred stock, $5 par value 59,000 59,000 Common stock, $0.25 par value 104,600 103,800 Retained earnings 4,194,590 3,660,515 Total stockholders' equity 4,358,190 3,823,315 Total liabilities and stockholders' equity $11,229,790 $10,562,015 Crane Medical Comparative Income Statement and Statement of Retained Earnings For the Year 2020 2019 Sales revenue (all on account) $10,177,250 $9,613,950 Cost of goods sold 5,612,450 5,298,750 Gross profit 4,564,800 4,315,200 Operating expenses 2,840,200 2,634,100 Net operating income 1,724,600 1,681,100 Interest expense 300,350 308,650 Interest expense 300,350 308,650 Net income before taxes 1,424,250 1,372,450 Income taxes (30%) 427,275 411,735 Net income $996,975 $960,715 Dividends paid Preferred dividends 29,450 29,450 Common dividends 433,450 413,100 Total dividends paid 462,900 442,550 Net income retained 534,075 518,165 Retained earnings, beginning of year 3,660,515 3,142,350 Retained earnings, end of year $4,194,590 $3,660,515 Calculate the following profitability ratios for 2020. (Round answers to 1 decimal place, e.g. 50.1%.) % a. Gross margin percentage % b. Return on assets % C. Return on common stockholders' equity