Suppose there is a 20% tax on the first $15,000 of taxable income, a 30% tax on taxable income above $15,000 until $30,000, and a 400 tax on all taxable income above $30,000. There is a $3,000 standare deduction and a $2,000 child tax credit. What is the marginal tax rate for a single mother of one child making $32,000? 20% 30% 40% 16.25%