1,000,001: One to change the bulb and 1,000,000 to rebuild civilization to the point where they need light bulbs again.
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Two — one to screw it most of the way in and the other to give it a surprise twist at the end.
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Two, one to call the electrician, and one to mix the drinks.
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They screw millions of bulbs every day, but when it comes to your bulbs, there's no record.
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