Problem: Given the question: Generate a question about the topic "Computed tomography angiography" whose answer would be: Computed tomography angiography (CTA) is a computed tomography technique used to visualize arterial and venous vessels throughout the body..
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The answer is:
what is cta used for?

input question: Generate a question about the topic "Stevie Ray Vaughan" whose answer would be: On August 27, 1990, Vaughan was killed in a helicopter crash following a performance in East Troy, Wisconsin ..???
output answer: what happened to stevie ray vaughan?

Generate a question about the topic "Black hairy tongue" whose answer would be: Black hairy tongue (BHT, also termed lingua villosa nigra) refers to a condition of the tongue where the filiform papillae elongate with black or brown discoloration, giving a black and hairy appearance..
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Answer: what is black hairy tongue disease?

Q: Generate a question about the topic "Kris Humphries" whose answer would be: Kris Nathan Humphries (born February 6, 1985) is an American professional basketball player with the Brooklyn Nets ..
A: who does chris humphries play for?

Question: Generate a question about the topic "PlayStation 3 launch" whose answer would be: The launch of the PlayStation 3 into the Japanese market on 10 November 2006 marked the second major seventh generation entertainment system to be released..
Answer: when did playstation 3 first launch?

Please answer this: Generate a question about the topic "Cellular respiration" whose answer would be: Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products..
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Answer:
what is feedback mechanism in plants during respiration?