OMG! That is laugh-out loud funny.
How many Cornies does it take to replace a light bulb?
Thousands. But they work for free and don't need to be fed or housed.
None. Light bulbs are self-replicating, formed from the gooey nougat that leaks up from between the floor boards.
Only two, but those two can replace all the world's light bulbs simultaneously. From one ladder. Using very long horizontal light-bulb grippers and high-pressure hoses.
You've asked the wrong question. The Stone Age didn't end for lack of stones. Light bulbs will be replaced when something better comes along.
You've asked the wrong question. The light bulb doesn't really matter because there is this Report, printed on fancy expensive Harvard University Stationary, and it's from this Really Important Guy. The Guy told me not to worry, it's night time. And it's really really dark in here.
And besides, I don't have the technical degree to understand it, so I am going back to bed.