1.6 Present value 17. The two sets of grandparents for a newborn baby wish to invest enough money immediately to pay $10,000 per year for four years toward college costs starting at age 18. Grandparents A agree to fund the first two payments, while Grandparents B agree to fund the last two payments. If the effective rate of interest is 6% per annum, find the difference between the contributions of Grandparents A and B