If you could earn 9% on similar-risk investments, what is the least you would accept at the end of a 6-year period, given the following amounts and timing of your investment?
a. Invest $5,000 as a lump sum today.
b. Invest $2,000 at the end of each of the next 5 years.
c. Invest a lump sum of $3,000 today and $1,000 at the end of each of the next 5 years.
d. Invest $900 at the end of years 1, 3, and 5.