John (age 60 and single) has earned income of $3,600. He has $35,800 of unearned (capital gain) income.

1) If he does not participate in an employer-sponsored plan, what is the maximum deductible IRA contribution John can make in 2015?

2) If he does participate in an employer-sponsored plan, what is the maximum deductible IRA contribution John can make in 2015?

3) If he does not participate in an employer-sponsored plan, what is the maximum deductible IRA contribution John can make in 2015 if he has earned income of $18,400?