A young woman got off a ship and sat down beside a young man.He wanted to play a game to kill time after a ship set off.He said,"let's ask about each other one question.If you don't know the answer,then you gave me five dollars." So I don't know the answer,you’ll get ten dollars." he added .The woman agreed.After failed to answer the man‘s question ,she asked,"What goes up a mountain with three legs ang come back with four?" The young man didn't know the answers .so he gave the woman ten dollars."How is this answer?" he asked .The woman took out her purse ,found five dollars ang gave the money the young man.