None. Bill Gates will just redefine Darkness® as the industry standard.
or
Five. Four to decide which way the bulb ought to turn, and . . .
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Because there's no one else to wag it for him.
or
The owner got tired of the (w)hole business!
or
A pork chop.
or
100: One to do it and ninety-nine to say "I could've done that."
or