A steel pipe is being carried down a hallway 9 ft wide. At the end of the hallway there is right angled turn into a narrower hallway 6 ft wide. What is the length of the longest pipe that can be carried horizontally around the corner?
| A. 18.49 ft |
C. 20.71 ft |
| B. 21.07 ft |
D. 19.84 ft |
