Two. One to hold the bulb and the other to rotate the planet.
or
Seven. One to change it and the other six to sing about how good the old one was.
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The entire team! And they all get a semester's credit for it!
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Two. One to take notes while the other screws it into the faucet.
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Because Mercury moved in.
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They both come in tots.
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So he could grade his eggs.
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He took them to a pignic.
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None. They have machines to do that now.
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A milkshake
or