One's a spineless, poisonous blob. The other is a form of sea life.
or
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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He made sure his pools were clean and his lawns were mowed.
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Five: one to handle the bulb and four to contemplate how David Sanborn would've done it.
or