Jennifer and Paul, who file a joint return, have taxable income of $82,825 and the following tax liability:

$19,400 × 10% = $ 1,940.00

($78,950 − $19,400) × 12% = 7,146.00

($82,825 − $78,950) × 22% = 852.50

Total tax liability $ 9,938.50

Their marginal tax rate is:

a. 10%.

b. 12%.

c. 13%

d. 22%.