Donkey Laugh

A guy is walking down the street when he notices a sign on a window front that says 'MAKE A DONKEY LAUGH AND WIN $5,000'. So the guy walks into the store and asks about it. The clerk tells him about the donkey in the back room. So the guy goes ahead and goes back. When he comes out of the room the donkey is laughing histerically. The clerk was shocked, but nevertheless hands over the $5,000 prize money. A week goes by and the same guy sees another sign except this time to make a donkey cry and the prize money is doubled to $10,000. He goes in and already knows the routine, so he goes into the back room. When he comes back out the donkey is completely bawling his eyes out. The clerk is absolutely stunned. He asks them man how he made the donkey laugh and cry. The man says, "To make him laugh I told him my dick was bigger than his. To make him cry I proved it."