Assume that your parents wanted to have $120,000 saved for college by your eighteenth birthday and they started saving on your first birthday. They saved the same amount each year on your birthday and earned 9% per year on their investments.

a. How much would they have to save each year to reach their​ goal?
b. If they think you will take five years instead of four to graduate and decide to have $ 160 comma 000$160,000 saved just in​ case, how much would they have to save each year to reach their new​goal?