4. Josh and Ann are saving up for their daughters college education. Seventeen years from today, they will have to pay $21,000 for her first year of school. Each year after that, the cost will rise by 4% per year. If their daughter takes 5 years to graduate, how much must they set aside every year from now UNTIL SHE GRADUATES to pay for her education? Assume they can earn 6% per year on their savings. You must draw a correct cash flow diagram to get full credit for this problem.