Two — one to screw it most of the way in and the other to give it a surprise twist at the end.
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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.
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Only one, but they get three tech. reports out of it.
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An embarrased mime!
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One. No, two. No... How many do we have on the truck?
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