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.
or
Five. One to change the bulb and eleven to say they could do it faster.
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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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but I'd never seen herbivore [her before]
or