In 2022 Courtney paid $3,500 in Ohio state income taxes, and the included this payment with her other itemized deductions when she filed her federal income tax return in March of 2024. Courtney filed her 2022 federal return as a head of household and claimed $21.500 of itemized deductions (including $3,500 state income taxes, $2,500 of real estate taxes, $8,000 of mortgage interest expense, and $7,500 of charitable contributions). She also filed an Ohio state income tax return in March of 2023 and discovered she only owed $3,080 in Ohio income tax for 2022. Hence, Courtney received a $420 refund of her Ohio income tax in June of 2023. 

Under the tax benefit rule, how much of the $420 refund should Courtney include in her gross income for 2023 given that the standard deduction for head of household filing status in 2021 was $19,4007 (show your work)