Mister Greenjeans wants to borrow

$2.8 million to purchase farm land to grow soy beans. He has approached the agriculture services division at his bank to arrange a farm mortgage. The bank has quoted him a rate of

8% over a 25 year amortization with quarterly payments of $64,532 Mister Greenjeans anticipates that he will have to borrow an additional

$0.56 million after 15years for land improvement costs. This extra principal will be added to the balance owing on the mortgage. If Mister Greenjeans continues making quarterly payments shown above, how long will it take him to pay off the mortgage? (Express your answer in years and round to the nearest integer value.)

(If using excel to solve please explain in depth on how and what formulas were used)