If one side has one, the other side has to get one. Once launched, they cannot be recalled. When they land, they screw up everything forever.
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None, but it takes at least one to sit and pray for the old one to go back on.
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None. They just let Marketing explain that "Dead Bulb" is a feature.
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Four. One to change the bulb and three to whine "It's too high"
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A sponge!
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