Sarah, who was divorced in 2019 and has a child that will be 6 at the end of 2021, has calculated her taxable income as $135,000. Her company withheld $21,000 for federal income taxes for the year. Her child lives with her in an apartment, but her ex-husband furnished over 75% of the child's support with child support payment. a. what is Sarah's filing status? b. what is the amount of Sarah's tax liability before the child tax credit? c. what is the amount of Sarah's child tax credit? d. what is Sarah's tax liability after the child tax credit but before considering her prepayments (withholdings)? e. what is Sarah's average tax rate (to the nearest tenth of a percent)? f. what is Sarah's tax due or refund amount? a