52 Exercise 4 53 Assuming that the interest rate is 8%, which of the following is more valuable? 54 (a) $5,500 today. 55 (b) $8,000 at the end of five years. 56 (c) $7,000 at the end of four years. 57 (d) $450 a year in perpetuity (meaning forever), with the first payment at the end of this year