I was amazed, I never knew they worked.
or
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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Because the sea weed
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Fun-ny!
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None: they just deny that the bulb ever went out in the first place.
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Only one, but the bulb has got to really WANT to change.
or