hi, can you please provide answers to this question with work to show for. thank you!

My pension plan will pay me $10,000 once a year for a 10 -year period. The first payment will come in exactly five years. The pension fund wants to immunize its position. Required: a. What is the duration of its obligation to me? The current interest rate is 10% per year. b. If the plan uses 5-year and 20-year zero-coupon bonds to construct the immunized position, how much money ought to be placed in each bond? c. What will be the face value of the holdings in each zero