Carl and Karina file a joint return. Karina earned a salary of $39,250 and received dividends of $3,100, taxable interest income of $2,050, and nontaxable interest of $1,025. Carl received $9,200 of social security benefits and a gift of $6,050 from his brother. What amount of social security benefits is taxable to Carl and Karina? Taxable social security benefits