[Q]: Sentence: The continuous torque density of conventional electric machines is determined by the size of the air-gap area and the back-iron depth, which are determined by the power rating of the armature winding set, the speed of the machine, and the achievable air-gap flux density before core saturation. Question: What does continuous torque density refer to?
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[A]: no

[Q]: Sentence: This was done to prevent the proliferation of secret treaties that occurred in the 19th and 20th century. Question: In which centuries did a proliferation of secret treaties occur that led the United Nations Charter to include an obligation to register treaties to be invoked before it?
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[A]: yes

[Q]: Sentence: Today, the country is known by wine lovers and its wines have won several international prizes. Question: Which two Portuguese wines are especially enjoyed around the world?
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[A]:
no