A couple are planning to save money for their children go to college 9 years' later. They currently have $175,000 which is deposited in the bank now. If they would like to have $1,750,000 when their children to go to college, what monthly rate of interest would they have to earn on their $175,000 in order to reach their goal? 2.15% 2.43% 2.51% 3.9%