Twenty. One to hold the bulb, two to turn the ladder, and 17 to be on the guest list.
or
In Washington, D.C.
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Five: One to change the bulb and four to pull the ladder out from under him/her.
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The cow that jumped over the moon
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They cell it.
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Because sometimes you can get rid of cancer.
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Stinker Bell.
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They stamp their feet.
or