It'll come back to me.
or
When it's going cheep!
Did you hear the one about the crow and the telephone pole?
He wanted to make a long distance caw.
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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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Because her mom would make her take it back.
or