Jane is a single taxpayer with a current year AGI of $181,000 and current year income tax liability of $34,968. Her AGI in the prior year was $150,400 and prior year tax liability was $27,247. Jane earns her income ratably during the year. In order to avoid penalty, the smallest amount of required annual withholding and estimated payments is:
a. $27,247
b. $29,972
c. $31,471
d. $34,968
e. $35,400