Solve the following rate of return problems. a. An investment of $1,500 today returns $55,000 in 50 years. What is the internal rate of return on this investment? b. An investment costs $850,000 today and promises a single payment of $12.1 million in 22 years. What is the promised rate of return, IRR, on this investment? c. What return do you earn if you pay $22,950 for a stream of $6,000 payments lasting 10 years