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
He had in his own pews.
or
1,000,001: One to change the bulb and 1,000,000 to rebuild civilization to the point where they need light bulbs again.
or
Five. One to screw it in and four to tell him how bitchin' he looked doing it.
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2 years old.
Cow: "Mooooove over"
Sheep: "Naaaaaaa."
or