The price of a car is $50,000 today. Its price is expected to increase by $2400 each year. You now have $25,000 in an investment that is earning 20% per year. The number of years before you have enough money to buy the car, without borrowing any money, is closest to:
(a) 3 years
(b) 5 years
(c) 7 years
(d) 9 years