Three, One to climb the ladder. One to shake it. And one to sue the ladder company.
or
The players dribble a lot.
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Two. One to hold the bulb and the other to rotate the planet.
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Two… one to tell the engineer to do it, the other to say "I don't know, what do you think?"
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Because it would fall over if it lifted the other one.
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I've got you covered!
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Holes.
or