Pierre, a cash basis, unmarried taxpayer, had $1,400 of state income tax withheld during 2021. Also in 2021, Pierre paid $455 that was due when he filed his 2020 state income tax return and made estimated payments of $975 towards his 2021 state income tax liability. When Pierre files his 2021 Federal income tax return in April 2022, he elects to itemize deductions, which amount to $15,650, including the state income tax payments and withholdings, all of which reduce his taxable income. a. What is Pierre's 2021 state income tax deduction? $ b. As a result of overpaying his 2021 state income tax, Pierre receives a refund of $630 early in 2022. The standard deduction for single taxpayers for 2021 was $12,550. How much of the $630 will Pierre include in his 2022 gross income