input question: Determine the topic of the question-answer pair. Question: "who rules communism government?"; Answer: "It has a form of government characterized by single-party rule or dominant-party rule of a communist party (referred as Dictatorship of the Proletariat by its proponents) and a professed allegiance to a Leninist or MarxistLeninist ideology as the guiding principle of the state."? Topic:???
output answer: Communist state

Determine the topic of the question-answer pair. Question: "how does a solid state drive work?"; Answer: "It uses an external power supply to make the DRAM non-volatile."? Topic:
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Answer: Solid-state drive

Q: Determine the topic of the question-answer pair. Question: "what is puerto rico currency?"; Answer: "The peso and dollar have been followed by other contemporary issues, including commemorative banknotes, private currency, and a quarter coin designed with Fort San Felipe del Morro in the face."? Topic:
A: Currencies of Puerto Rico

Question: Determine the topic of the question-answer pair. Question: "what is file based system?"; Answer: "In computing , a file system (or filesystem) is a type of data store which can be used to store, retrieve and update a set of files ."? Topic:
Answer: File system

[Q]: Determine the topic of the question-answer pair. Question: "what is the format of the canadian citizenship test?"; Answer: "The test is available in both French and English , the official languages of Canada ."? Topic:
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[A]: Canadian Citizenship Test

Problem: Given the question: Determine the topic of the question-answer pair. Question: "how are aircraft radial engines built?"; Answer: "The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes of a wheel."? Topic:
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The answer is:
Radial engine