A proud and confident professor makes a bet with an under-performing student. The professor says, "Every question I ask you that you don't know the answer, you have to give me $5. And if you ask me a question and I can't answer yours, I will give you $5,000."
The student agrees and the professor asks, "How many continents are there in the world?" The student doesn't know and hands over the $5. The student says, "Now my turn, what animal stands with two legs but sleeps with three?"
The professor thinks very hard for the answer, but his face falls as he gives up and hands over the $5000. He says, "Wow, I lost. I must know, what was the answer to your question?"
Smiling, the student hands over $5