Einstein and Banta are sitting next to each other on a long flight. Einstein says, "Let's play a game. I will ask you a question. If you don't know the answer, you pay me only $ 5 and if I don't know the answer, I will pay you $500." Einstein asks the first question: What's the distance from the Earth to the Moon? Banta doesn't say a word, reaches his pocket and pulls out a $ 5. Now, it's Banta's turn. He asks Einstein, "What goes up a hill with 3 legs and comes down on 4 legs?" Einstein searches the net and asks all his smart friends. After an hour, he gives Banta $500. Einstein going nuts and asks, "Well, so what goes up a hill with three legs and comes down with four?" Banta reaches his pocket and gives Einstein $ 5.