4. Gregor will receive $20,000 at the end of 6 years. If the interest rate is 7% per year, what is the present value of this cash flow? (3 points) 5. A perpetuity will pay you $400 per year, forever. If the discount rate is 8%, what is this perpetuity worth today? (3 points) 6. Nicole will need $22,000 in nine years. She currently has $10,000 to invest. At what interest rate must she invest the money? (3 points)