Given an trivia question precisely answer the question with a word/phrase/name. External resources such as Wikipedia could be used to obtain the facts.
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Question: What word is used in mathematics to mean if and only if?

Answer: if and only if


Question: Which group won the Mercury Prize in 2008 for their album 'The Seldom Seen Kid'?

Answer: elbow


Question: Alban Berg's opera 'Lulu' ends with the appearance of which murderer?

Answer:
jack the ripper