A young engineer decides to save $240 per year toward retirement in

40 years.

1. If he invests this sum at the end of every year at 9%, then how

much will be accumulated by retirement time?

2. If by astute investing the interest rate could be raised to 12%, then

what sum could be saved?

3. If he deposits one fourth of this annual amount each quarter ($60

per quarter) in an interest bearing account earning a nominal annual

interest rate of 12%, compounded quarterly, how much could be

saved by retirement time?

4. In part (c), then what annual effective interest rate is being earned