I need some helping walking through the steps of this problem. It is just a practice problem given to me by my teacher's assistant and I am not sure how to calculate the NPV with the change in return rates or where to use the inflation rate.

You are planning to retire at the age of 65. You think you will live for 5 years after you retire, and you will need $50,000 per year (today's value) at the beginning of each year for your retirement. While you are working, you will put your money in funds which give you an average return of 8%. After you retire, you will put your money in safer funds that give you a 3.5% return. The inflation rate is 2%. You just turned 25 years old today and you will contribute to the funds at the end of each month until you retire with an initial investment of $5,000 today. Assume that the safer funds compound annually and the 8% funds compounded monthly.

How much in total do you have to have in your account when you retire at the age of 65?