Mr. and Mrs. Davos file a joint tax return. Each spouse contributed $3,800 to a traditional IRA. In each of the following cases, compute the deduction for these contributions. The AGI in each case is before any deduction.

a. Neither spouse is an active participant in a qualified retirement plan, and their AGI is $123,400.

b. Mr. Davos is an active participant, but Mrs. Davos is not. Their AGI is $123,400.

c. Both spouses are active participants, and their AGI is $89,200.

d. Mr. Davos is self-employed and doesn't have a Keogh plan. Mrs. Davos is an active participant. Their AGI is $109,400.

Assume the taxable year is 2018.