All the responses given are the correct answers. I responses that have a red corner are the ones I got wrong, but they provided the correct answer. My problem is I still don't know how they got those answers. If you could take me through the steps to solve this problem, please.

Piper is a participant in a qualified pension plan. She retires on January 1, 2020, at age 61, and receives pension payments beginning in January 2020. Her pension payments, which will be received monthly for life, amount to $2,600 per month. Piper contributed $78,000 to the pension plan on a pre-tax (or tax-deferred) basis, and the number of anticipated payments based on Piper's age of 61 years is 260 months (see IRS table) from the date she starts receiving payments. Read the requirements. Requirement a. What gross income will Piper recognize in 2020 and each year thereafter? Piper will recognize $ 31,200 of gross income in 2020 and each year thereafter. Requirement b. How would your answer to Part a change if Piper made contributions to the plan on an after-tax basis? (Round intermediary calculations and final answers to the nearest cent.) simplified method for qualified retirement plan annuities. Piper will The pension payments will be taxed under the recognize $ 27,600.00 of income. Requirement c. If, in Part b, Piper dies in December 2021 after receiving pension payments for two full years, what tax consequences occur in the year of death? (Round intermediary calculations and final answers to the nearest cent.) Piper's final return in 2021 will include $ 27,600.00 of income from the pension payments and an itemized deduction for the unrecovered investment in the contract of $ 70,800.00 a. What gross income will Piper recognize in 2020 and each year thereafter? b. How would your answer to Part a change if Piper made contributions to the plan on an after-tax basis? C. If, in Part b, Piper dies in December 2021 after receiving pension payments for two full years, what tax consequences occur in the year of death