One. They're efficient and don't have humour.
Schweinsteiger.
A Munich
To get to the otherside!
Two. One to put it in and one to complain that he never screws anything anymore.
5. 1 to screw in the light bulb, and 4 to remark on how grand the old one was.
3. One to change the bulb and two to talk about how beautiful the turns were.
Because it's inefficient!