21. How much more is a perpetuity of $1000 worth than an annuity of the same amount for 20 years? Assume an interest rate of 5% and cash flows at the end of each period.

22. A perpetuity-immediate pays X per year. Brian receives the first n payments, Colleen receives the next n payments, and Jeff receives the remaining payments. Brians share of the present value of the original perpetuity is 40%, and Jeffs share is K. Calculate K.