Pierre, a cash basis, unmarried taxpayer, had $1,400 of state income tax withheld during 2015. Also in 2015, Pierre paid $455 that was due when he filed his 2014 state income tax return and made estimated payments of $975 towards his 2015 state income tax liability. When Pierre files his 2015 Federal income tax return in April 2016, he elects to itemize deductions, which amount to $10,650, including the state income tax payments and withholdings, all of which reduce his taxable income.
a. What is Pierre's 2015 state income tax deduction?
b. As a result of overpaying his 2015 state income tax, Pierre receives a refund of $630 early in 2016. The standard deduction for single taxpayers for 2015 was $6,300. How much of the $630 will Pierre include in his 2016 gross income?