Your sister paid $10,000 (CF at t = 0) for an investment that promises to pay $750 at the end of each of the next 5 years, then an additional lump sum payment of $10,000 at the end of the 5th year. What is the expected rate of return on this investment? a. 8.27% b. 7.50% c. 7.88% d. 6.77% e. 7.13%