Answer:
A boy throws a baseball. It travels 40 feet and then goes right back to the boy. How is that possible?
When is homework not homework?
Which bank is not used for storing money?
Three doctors said that Bill was their brother. Bill said he had no brothers. Who was lying?
There are two sisters: one gives birth to the other and she, in turn, gives birth to the first. Who are the two sisters?
What never gets any wetter no matter how hard it rains?