Wildhorse Medical manufactures hospital beds and other institutional furniture. The company's comparative balance sheet and income statement for 2019 and 2020 follow. Wildhorse Medical Comparative Balance Sheet As of December 31 2020 2019 Assets Current assets Cash $367,000 $417,500 Accounts receivable, net 1,026,000 776,450 Inventory 717,000 681,000 Other current assets 381.350 247,100 Total current assets 2,491,350 2,122,050 Property, plant, & equipment, net 8,766.955 8,439.995 Total assets $11,258.305 $10,562,045 Liabilities and Stockholders' Equity Current liabilities $3,198,000 $2,846,100 Long-term debt 3,702,650 3,892,600 Total liabilities 6,900,650 6,738,700 Preferred stock, $5 par value 58.900 58,900 Common stock, $0.25 par value 104,700 103.850 Retained earnings 4,194.055 3,660,595 Total stockholders' equity 4,357,655 3,823,345 Total liabilities and stockholders' equity $11,258.305 $10,562,045Wildhorse Medical Comparative Income Statement and Statement of Retained Earnings For the Year 2020 2019 Sales revenue (all on account) $10,177,200 $9,613,950 Cost of goods sold 5,613,250 5,298.800 Gross profit 4,563,950 4,315,150 Operating expenses 2,840,250 2,634,200 Net operating income 1,723,700 1,680,950 Interest expense 300,400 308,600 Net income before taxes 1,423,300 1,372,350 Income taxes (30%) 426,990 411,705 Net income $996,310 $960,645 Dividends paid Preferred dividends 29.450 29.450 Common dividends 433,350 413,000 Total dividends paid 462,800 442,450 Net income retained 533.460 518.195 Retained earnings, beginning of year 3,660.595 3,142,400 Retained earnings, end of year $4,194,055 $3,660,595 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 9% c. Return on common stockholders' equity