Why are ducks funny?

“Wanna buy a duck?"
—Joe Penner

Q: What’s the difference between a duck?
A: Each of its legs is both the same?
—My Father

Two ducks are sitting in a bathtub.
The first duck says, “Please pass the soap,”
The other duck says, “No soap, radio.”
—Unknown

“Why a duck?”
—Chico Marx

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