Carla Vista Medical manufactures hospital beds and other institutional furniture. The companys comparative balance sheet and income statement for 2019 and 2020 follow. Carla Vista Medical Comparative Balance Sheet As of December 31 2020 2019 Assets Current assets Cash $395,000 $417,400 Accounts receivable, net 1,054,000 776,500 Inventory 728,000 681,100 Other current assets 381,300 247,100 Total current assets 2,558,300 2,122,100 Property, plant, & equipment, net 8,661,970 8,439,780 Total assets $11,220,270 $10,561,880 Liabilities and Stockholders Equity Current liabilities $3,160,000 $2,846,000 Long-term debt 3,702,600 3,892,700 Total liabilities 6,862,600 6,738,700 Preferred stock, $5 par value 58,900 58,900 Common stock, $0.25 par value 104,650 103,850 Retained earnings 4,194,120 3,660,430 Total stockholders equity 4,357,670 3,823,180 Total liabilities and stockholders equity $11,220,270 $10,561,880 Carla Vista Medical Comparative Income Statement and Statement of Retained Earnings For the Year 2020 2019 Sales revenue (all on account) $10,177,300 $9,613,900 Cost of goods sold 5,613,000 5,298,700 Gross profit 4,564,300 4,315,200 Operating expenses 2,840,200 2,634,200 Net operating income 1,724,100 1,681,000 Interest expense 300,400 308,600 Net income before taxes 1,423,700 1,372,400 Income taxes (30%) 427,110 411,720 Net income $996,590 $960,680 Dividends paid Preferred dividends 29,550 29,550 Common dividends 433,350 413,000 Total dividends paid 462,900 442,550 Net income retained 533,690 518,130 Retained earnings, beginning of year 3,660,430 3,142,300 Retained earnings, end of year $4,194,120 $3,660,430 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 %