Using the 2018 tax schedule/ Chuck, a single taxpayer, earns $132,500 in taxable income and $18,500 in interest from an investment in City of Heflin bonds. (Use the U.S. tax rate schedule.) Required: If Chuck earns an additional $42,800 of taxable income, what is his marginal tax rate on this income? What is his marginal rate if, instead, he had $42,800 of additional deductions?