Susan is single with 2020 gross income of $120,000 and a taxable income of $98,000. In calculating gross income, she properly excluded $10,000 of tax-exempt interest income a. c. The marginal tax rate is the rate of tax that would be paid on the next dollar of income b. The average tax rate is the rate of tax paid on the total tax base The effective tax rate is the rate of tax paid on all income Instructions: Do not round intermediate computations. Round final answers to two decimal places. Refer to Appendix D for calculations. d. Susan's total tax is s Her marginal tax rate is %, and, effective tax rate is %, average tax rate is