1. Toni is looking at an investment that requires a payment of $3,152 now, in order to get a $10,000 lump sum payment at the end of 15 years. What is the Internal Rate of Return (IRR) for this investment. Remember that the IRR is the interest rate that makes the NPV equal to zero.

2. Lena has been offered the possibility of investing $42,410 now. The investment will earn 10% per year and at the end will pay Lena $100,000. How many years will it take?

3. Nora purchased an investment for $12,462. From this investment, she will receive $1,000 annually for the next 20 years. What rate of interest will Nancy's investment be earning?