None. It's too dark.
Three. One to do it, one to complain that it has already been done before, and one to repost this joke.
Three to screw it in and Bono to explain it to the world.
To change his jockeys.
None, because they keep on asking why all of the other light bulbs in the house aren't being changed at the same time.
Mr Macawber and Pollyanna!
