Katalin drove 210 miles on her vacation. She drove an average of 1.4 times faster on the second 105 miles of her trip than she did on the first 105 miles of her trip. Which expression represents the time she spent driving? Let x = her speed on the first half of the trip.
A. 180x
B. 360 divided by x.
C. 252 divided by x.
D. 180 divided by x.