[Q]: Sentence: The corresponding reaction leading to the formation of magnetite (Fe_3O_4), quartz (SiO_2) and hydrogen (H_2) is the following: Question: Where do you find silicate?
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[A]: no

[Q]: Sentence: The army had substantially left the city by 1971, with barracks pulled down in the 1960s, however the city remains home to the 42 Commando of the Royal Marines. Question: By what year was the greater part of the army presence in Plymouth gone?
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[A]: yes

[Q]: Sentence: Chief among these is maize or "corn", arguably the most important crop in the world. Question: What type of bean is used to make chocolate?
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[A]:
no