Pierre, a cash basis, unmarried taxpayer, had $3,500 of state income tax withheld during 2023. Also in 2023 , Pierre paid $875 that was due when he filed his 2022 state income tax return and made estimated payments of $2,450 towards his 2023 state income tax liability. When Pierre files his 2023 Federal income tax return in April 2024, he elects to itemize deductions, which amount to $18,150, including the state income tax payments and withholdings, all of which reduce his taxable income. a. What is Pierre's 2023 state income tax deduction? $ b. As a result of overpaying his 2023 state income tax, Pierre receives a refund of $1,400 early in 2024. The standard deduction for single taxpayers for 2023 was $13,850. How much of the $1,400 will Pierre include in his 2024 gross income? $