One. But he gets three hours credit.
Two. One to hold it in the socket and the other to drink until the room starts spinning!
Two. One to hold the bulb, and another to spin the story until the bulb fits.
Who wants to know
One, but it takes at least three light bulbs.
when you realize that you have had 2 strepsils within one hour.
You need to give a three hour lecture and turn in a research paper on "What is 'good' " first.