Please! I need help with this question. I could not figureout the Preliminary Net Income and Net Profit Margin. I need help, please!

Thank you

epare an unadjusted trial balance at the end of February BARB'S BOOK BUSINESS Unadjusted Trial Balance At February 28 Credit Debit Account Name 20,130 Cash 2,136 Accounts Receivable 330 Supplies 2,625 Prepaid Rent 10,200 Land 5400 Equipment 15,600 Notes Payable (long-term) 23,000 Common Stock Service Revenue 3,950 740 Advertising Expense 850 Salaries and Wages Expense 139 Repairs and Maintenance Expense Total 42,550 42,550