The One The Morning After - S3-E16
Continuity mistake: In previous episodes we've seen that from the living room there's a short wall just inside Monica's bedroom (presumably to prevent a clear view inside, as her bedroom set isn't normally there). However in this episode when most of the gang are in her room, they're listening right by the door into the living room with nothing in the way. (00:11:25)
Chosen answer: It was not a bugs Bunny cartoon. It was a Tex Avery cartoon. Tex Avery's Musical Maestro (1951) Here is the write up: http://comics.ign.com/articles/649/649921p1.html.
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