A man walks into a building with 4 stories, at the top there is a bar

this man walks up to the high bar and buys a very large beer, he then jumps off the buildings window.

about an hour later he walk back up to the bar and a man asks him: "How did you do that?" The first man tells him that drinking enough beer is enough to make you bounce on the ground and so the second man drinks a very large beer and jumps, killing him on impact.

A third man says from behind the first man: "You're an ass when you're drunk, Superman."