Individuals Campbell, a single taxpayer, earns $402,500 in taxable income and $2,200 in interest from an in (Use the U.S. tax rate schedule). Required: a. If Campbell earns an additional $15,500 of taxable income, what is her marginal tax rate on th b. What is her marginal rate if, instead, she had $15,500 of additional deductions? Note: For all requirements, do not round intermediate calculations. Round percentage ans r11]