A couple decides to save money for their child's first-year college tuition. The parents will deposit 3000 after n months from today and another 4000 after 2n months from today. All deposits earn interest at a nominal annual rate of 4.8%, compounded monthly. Calculate the maximum integral value of n such that the parents will have accumulated at least 9000 after seven years from today. O 11 O 12 13 16 O 17