Seven months old.
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From 2nd to 3rd because there's a shortstop in the middle.
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One; she designs the bulb to crawl up the wall, unscrew the old one, and screw itself in.
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The question is irrelevant, since you couldn't find the dolls even if you knew how many. (Note: Well, this was a good joke in 1983-84. . . .)
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