How do I go about showing my work on these questions? The red letters are the answers but not sure how to solve for these. Thanks in advance!

Use the following tax information to answer questions 1 - 2. Income Bracket Marginal Tax Rate $ 4,550.00 9.50% S 4,551.00 $ 7,950.00 18.75% 7,951.00 $ 18,000.00 34.50% $ 18,001.00 28,500.00 50.00% $ 28,501.00 or Higher 66.85% Additional Surtax: 15% on income between $ 15,000.00 and $ 17,500.00 5% on income between $ 25,000.00 and $ 35,000.00 1. Before Covid-19 restrictions, Marissa Education Inc. has taxable income of $30,000. The total tax liability of the company is closest to A) $10,453.80 H B) $10,828.80 C) $11,413.05 D) $11,752.80 2. After Covid-19 restrictions, Marissa Education Inc. has taxable income of $18,800. The average tax rate of the company is closest to A) 27.11% B) 28.25% C) 31.59% Active D) 40.42%