Assume the rate on the issuance of $100m of 100-year bonds is 7.5%; the annual debt service payment would be $7.505m. How high would the interest rate have to be on 30-year bonds for the annual debt service payment to be the same for both financings?

A second way to assess the 100-year bond is to consider a $100m 30 year issue with a 5% rate. The present value of this cash flow stream is $100m, using a 5% discount rate. Suppose you use 5% as the discount rate to assess the present value of the cash flow stream of the 100- year issue. How many years would it take to reach $100m in present value?