Two. One to assume the ladder and one to change the bulb.
A': None. If the government would just leave it alone, it would screw itself in.
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A whole synod. One to move that the bulb be changed while the others debate until the room spins.
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Twenty. One to hold the bulb, two to turn the ladder, and 17 to be on the guest list.
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In sundae school.
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