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Question Answered, Topic Closed

Acronym can be found on message boards where moderators manually close threads once the question in thread has been answered. Therefore, it's usually the text of the last post in a thread (by the moderator).
Thread title: "How is .99999... = 1?"
*lots of discussion*
*proof shows up*
Moderator: QATC
*thread is closed*
by PseudoNoise August 29, 2006