You wish to retire in 30 years. You think that you will need an income $5,000 every month from an ordinary annuity. The current interest rate is 6% (compounded monthly). You wish to receive that payment for 23 years after retirement. a. What lump sum in 20 years will you require to purchase that annuity. b. How much must you contribute monthly starting today to be able to buy that annuity (6% compounded monthly) c. If you estimate the inflation rate will be 4% per year, what would the purchasing power of $5,000 every month in 30 years be in todays money.