Three - one to cast the bulb into the outer darkness, and two to catch it when it falls.
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They take short cuts!
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It ran out of juice!
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Well, first let's talk about the concept behind this whole "light bulb" thing.
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Because he wanted to be on time.
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Two. One to assure the everything possible is being done while the other screws the bulb into the water faucet.
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