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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Answer: what is cta used for?

Generate a question about the topic "Serenity Prayer" whose answer would be: The Serenity Prayer is the common name for an originally untitled prayer by the American theologian Reinhold Niebuhr (18921971)..
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Answer: who wrote serenity prayer?

Generate a question about the topic "List of districts of West Bengal" whose answer would be: In 1947, when India gained independence, the state of West Bengal was formed with 14 districts, as per partition plan of the then Bengal province of British India ..
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Answer:
how many district are in west bengal?