Hello please explain what equation you use and the steps thanks

2-13. One retirement vehicle is to purchase an annuity through your bank, in which you deposit a certain amount of money up front, and the bank makes regular payments to you based off that deposit. Suppose you purchase such an annuity for $300,000 at a nominal rate of 6.3%. Determine the expected monthly payments, if payments are guaranteed for 10 years. Note: Often this is offered as part of a life insurance policy, where your retirement income is guaranteed for life. You have the additional option of guaranteeing a number of years, so that if you die before that period expires, the estate continues to claim the income. This is much harder to simulate, since it requires actuarial data