Poet and Scientist

A poet and a scientist were traveling together on a plane. 

Scientist: I'll ask you a question, and if you get it wrong, you give me $5. Then, you ask me a question, and if I can't answer it, I'll give you $5."

Poet:  Sorry!! I am busy.

Scientist: Look, if you can't answer it, you give me $5, and if I can't answer it, I'll give you $50.

Poet:  Okay.

Scientist: What is the exact distance between the Earth and the Moon?

Poet: (took a $5 bill out of his pocket and handed it to the scientist.)

Scientist: Okay, now it's your turn.

Poet: (The poet thought about this for a few minutes, then asked) All right, what goes up a mountain on three legs, but comes down on four?

Scientist: (He thought about this for a long time, taking out his notepad and making numerous calculations. He finally gave up on his notepad and took out his laptop, using his Multimedia Encyclopedia. As the plane was landing the scientist gave up. He reluctantly handed the poet a $50 bill.)

Poet: (accepted it graciously, getting ready to stand up.)

Scientist: Wait! ,you can't do this to me! What's the answer?


Poet: (The poet looked at the scientist and calmly put a $5 bill into his hand.)