Problem Solving

Car B starts at point X and moves clockwise around a circular track at a constant rate of 2 mph. Ten hours later, Car A leaves from point X and travels counter-clockwise around the same circular track at a constant rate of 3 mph. If the radius of the track is 10 miles, for how many hours will Car B have been traveling when the cars have passed each other for the first time and put another 12 miles between them (measured around the curve of the track)?

A 4 \pi - 1.6
B 4 \pi + 8.4
C 4 \pi + 10.4
D 2 \pi - 1.6
E 2 \pi - 0.8