Only one, but she/he'll have to go out and buy the light bulb adaptor card first, which is extra.
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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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Bozo The Clown has real hair on his head.
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Executive Producers don't screw in a light bulb, they screw in a hot tub.
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In sundae school.
or