Dave and Alana are married and claim 4 exemptions. Last year Alana earned $31,300 and Dave earned $25,100 in wages. Additional tax information for the year is as follows: interest earned: $2,600; penalty on early withdrawal of savings: $200; contributions to IRA retirement fund: $2,500; real estate taxes paid: $2,500; mortgage interest paid: $6,800. Find the taxable income if they file a joint return.
a) $56,400
b) $35,700
c) $28,100
d) $41,700