Albert Einstein & Indian man- A Joke

Once Albert Einstein was sitting right next an indian man on a flight, Einstein told him that he is a great scientists from Germany. Einstein make a bet with him that "I will ask you a question and if you are not able to answer it then you will give me 5$,
then you ask me question and if am not able to answer then i will give u 500$.

The man thinks 5$ : 500$ seems like a good ratio so he says sure.

Einstein asks what is the distance between Earth and the moon?
The man hands over 5$ to him and replied I don't know.

Now its the Indian man turn to ask Einstein a question. He asks "which animal goes up a mountion with 3 legs and comes down with 4?"

Einstein thinks and thinks 🤔and finally hands over 500$ to the man.
The man took 500$ and went to sleep.

Einstein is so much annoyed😠, he woke up the man and said hey I had given you 500$ and just tell me
which animal goes up a mountion with 3 legs and comes down with 4?

The Indian man gives Einstein another 5$ and replied I don't know