Explain and show calculations to the following scenarios.

During the current year, John Johnson received a salary of $16,000 and interest income of $1,200 and contributed $1,600 to his IRA. What amount of the IRA contribution can be deducted in arriving at John's adjusted gross income?

Chris Delbert's employer had a Simplified Employee Pension (SEP) for its employees. Chris's compensation before his SEP contribution was $31,000. What is the maximum amount that Chris's employer can deduct as a contribution to an SEP-IRA on behalf of Chris for 2019?

Albert Hanes, a sole proprietor, had net earnings of $4,500 from self-employment and paid a self-employment tax of $600. What is Albert's maximum self-employment retirement plan deduction for 2019?

AJ and Holly are married and received salaries of $14,000 and $46,000, respectively. If they are both age 25 and file a joint tax return, what is the maximum they can contribute to an individual retirement savings program and deduct for the current year?

Bert Sanders is single and 28 years of age. He earned a salary of $78,000 in 2019 as a computer tech by Bart Company. Bert was covered for the entire year 2019 under Bart's qualified pension plan for employees. In addition, Bert had a net income of $11,000 from self-employment. What is the maximum amount that Bert can deduct in 2019 for contributions to an IRA?