Need help with 3 and 4

You have a $3,000 monthly loan payment. If annual inflation is 4% (compounded monthly), what is the constant dollar amount of this payment in your 70^th month? (Recall that since the annual inflation rate is compounded monthly and payments are made monthly, you can calculate the effective monthly inflation rate simply by dividing the annual inflation rate by 12). You need $80,000 today to live a comfortable lifestyle. If the annual inflation rate is 5%, how much would you need in actual dollars 40 years from now to have the same spending power