Please answer this: Determine the topic of the question-answer pair. Question: "What is an economic feature??"; Answer: "Other broad distinctions include those between positive economics (describing "what is") and normative economics (advocating "what ought to be"); between economic theory and applied economics ; between rational and behavioral economics ; and between mainstream economics (more "orthodox" and dealing with the "rationality-individualism-equilibrium nexus") and heterodox economics (more "radical" and dealing with the "institutions-history-social structure nexus")."? Topic:
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Answer: Economics

Please answer this: Determine the topic of the question-answer pair. Question: "what is an arc in a story plot?"; Answer: "A story arc is an extended or continuing storyline in episodic storytelling media such as television , comic books , comic strips , boardgames , video games , and in some cases, films ."? Topic:
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Answer: Story arc

Please answer this: Determine the topic of the question-answer pair. Question: "how many baseball teams usa?"; Answer: "It is composed of 30 teams 29 in the United States and one in Canada."? Topic:
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Answer:
Major league baseball