Does anyone know if I did most of these correctly? and I can not figure out how to get the return on common stockholders equity.

Selected current year-end financial statements of Cabot Corporation follow. All sales were on credit; selected balance sheet amounts at December 31 of the prior year were inventory, $48,900; total assets, $189,400; common stock, $90,000; and retained earnings, $33,748. CABOT CORPORATION Balance Sheet December 31 of Current Year CABOT CORPORATION Income Statement For Current Year Ended December 31 Assets Cash Short-term investments Accounts receivable, net Merchandise inventory Prepaid expenses Plant assets, net Total assets 10,000 8,400 33,700 32,150 2,650 153,300 240,200 Sales Cost of goods sold Gross profit Operating expenses Interest expense Income before taxes Income tax expense Net income 448,600 297,250 151,350 98,600 4,100 48,650 19,598 29,052 17,500 3,200 3,300 Liabilities and Equity Accounts payable Accrued wages payable Income taxes payable Long-term note payable, secured by mortgage on plant assets Common stock Retained earnings Total liabilities and equity 63,400 90,000 62,800 240,200 1.0 1.7 27.4 7.3 39.5 Compute the following: 1) Current ratio 2) Acid-test ratio 3) Days' sales uncollected 4) Inventory turnover 5) Days' sales in inventory 6) Debt-to-equity ratio 7) Times interest earned 8) Profit margin ratio 9) Total asset turnover 10) Return on total assets 11) Return on common stockholder's equity 57% 12.9 6% 2% 14%