All of them.
You cant count them when its dark
Hehe... 'screw' Alternatively: 69, but everyone expects that one.
As much people as is needed to screw that lightbulb.
One. They hold it in place and wait for the world to revolve around them.
Electricity
You hide their food stamps under their work boots. Edit Thank you /u/DoctorBrohoof for my first gold!