[Q]: Sentence: Due to these initiatives and others, the air quality in Mexico City has begun to improve, with the air becoming cleaner since 1991, when the air quality was declared to be a public health risk for 355 days of the year.[citation needed] Question: What do new cars in Mexico need to have?
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[A]: no

[Q]: Sentence: In 1881, Zion's Watch Tower Tract Society was presided over by William Henry Conley, and in 1884, Charles Taze Russell incorporated the society as a non-profit business to distribute tracts and Bibles. Question: Who presided over Zion's Watch Tower Tract Society in 1881?
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[A]: yes

[Q]: Sentence: There is considerable debate about who arrived first and Gray later challenged the primacy of Bell's patent. Question: On what date did Gray and Bell both put in for a patent?
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[A]:
no