In 2021 Madison received a $1,900 refund of state income taxes that she paid in 2020. She had paid $2,800 of state income taxes in 2020. The standard deduction amount in 2020 was $12,400. How much of the $1,900 refund, if any, must Madison include in gross income in 2021, under each of the following independent assumptions? a. If her total itemized deductions in 2020 were $13,500, including $2,800 of state income taxes TAXABLE REFUND b. If her total itemized deductions in 2020 were $14,400, including $2,800 of state income taxes TAXABLE REFUND c. If her total itemized deductions in 2020 were $12,000, including $2,800 of state income taxes TAXABLE REFUND