Two different methods are under consideration for building a bypass road. Material C will cost $100,000 per mile and last for 10 years. Its annual maintenance cost will be $10,000 per year per mile. Material D will cost $30,000 per mile and last for 5 years. At an interest rate of 6% per year, the annual maintenance cost for material D that will make the two methods cost the same is closest to:
(a) Less than $14,000
(b) $14,270
(c) $16,470
(d) $19,510