Answer the following independent questions with respect to traditional IRA contributions for 2021. 

a. Juan, age 41, earns a salary of $28,000 and is not an active participant in any other qualified plan. His wife, Agnes, has no earned income. What is the maximum total deductible contribution to their IRAs? Juan wants to contribute as much as possible to his own IRA.

b. Abby, age 29, reports earned income of $25,000, and her husband, Sam, has earned income of $2,600. They are not active participants in any other qualified plan. What is the maximum contribution to their IRAs?

c. Leo’s employer makes a contribution of $3,500 to Leo’s simplified employee pension plan. If Leo is single, has earned income of $32,000, and has AGI of $29,000, what amount, if any, can he contribute to an IRA?