Two. 1 to screw it in, and 1 to complain that it's not dark enough.
One. Five. One.
100, 1 to screw it in and 99 to say how they could do it better.
He needs to be very careful, because he may be getting screwed.
One to hold the lightbulb, and the rest of the world to revolve around them
The Tchernobyl cowboy.
Because they're too stupid to learn how to make them.