Pharoah Medical manufactures hospital beds and other institutional furniture. The company's comparative balance sheet and income statement for 2019 and 2020 follow. Pharoah Medical Comparative Balance Sheet As of December 31 2020 2019 Assets Current assets Cash $387,000 $417,400 Accounts receivable, net 1,075,000 776,500 Inventory 727,000 681,100 Other current assets 381,350 247,050 Total current assets 2,570,350 2.122,050 Property, plant, & equipment, net 8,651,785 8.439.645 Total assets $ 11,222,135 $10.561,695 Liabilities and Stockholders' Equity Current liabilities $3,162,000 $2.846,000 Long-term debt 3,702,600 3,892,600 Total liabilities 5,864,600 6.738,600 Preferred stock, $5 par value 58,900 58,900 Common stock, $0.25 par value 104,650 103,900 Retained earnings 4,193,985 3,660,295 Total stockholders' equity 4,357,535 3.823,095 Total liabilities and stockholders' equity $11,222,135 $10.561,695Pharoah 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 2.840,300 2,634.200 Net operating income 1,724,000 1,681.000 Interest expense 300,300 308.650 Net income before taxes 1,423,700 1,372,350 Income taxes (30%) 427,110 411.705 Net income $996,590 $960.645 Dividends paid Preferred dividends 29.550 29.550 Common dividends 433,400 413,100 Total dividends paid 462,950 442.650 Net income retained 533,690 517.995 Retained earnings, beginning of year 3.660,295 3,142,300 Retained earnings, end of year $4.193,985 $3,660.295 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