None, because people who glow in the dark don't need light bulbs.
Note: Topical to the Chernobyl Reactor disaster of 1984.
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Seven. One to install the new bulb and six to figure out what to do with the old one for the next 10,000 years.
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One in 3,000,000 has a chance of becoming a human being.
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Actually, agents will screw in just about anything.
or