Bret and Cindy took different routes to travel from Point A to Point E. Bret took the route along A, B, C, D, and E. Cindy took the route along A, F, and E and reached the destination in 2 hours. Their routes are shown. If Bret's average speed was twice Cindy's average speed, what was Bret's average speed?

3 miles per hour
6 miles per hour
8 miles per hour
9 miles per hour