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
No one knows. Republicans automatically disbelieve him, and no one can ever trust a stinking liberal anyway.
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None, because they were copycats
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6: 2 to screw in the bulb and 4 to testify that it was lit from the moment they began screwing.
or