Woah woah woah... I never said there was a lightbulb!
Twenty. 1 to drop it, 19 to go "Pick it up, pick it up, pick it up".
None. It will change when the fire nation attacks
Five. One to handle the bulb and 4 to contemplate how David Sanborn would've done it.
Two. One guy to screw in the light bulb, and the other guy to shoot him if he doesn't do it right.