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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Two, one to call Daddy, and one to get the (pick one:) mineral water/Tab.
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Hey, bud!
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Two. One to change the bulb, and one to write a song about how good the old light bulb was.
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Bike helmets don't fit hippos
or