Two… one to tell the engineer to do it, the other to say "I don't know, what do you think?"
or
They're both plastic and little boys turn them on.
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To get to the shell station.
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Because he was under cover.
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A traffic jam.
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Three. One to climb the ladder while the second kicks the ladder out from under her. And the third to say, "I knew that was too high for you dear."
or