[Q]: Sentence: When such mechanisms (or spiral screws or pneumatic transport) are used to elevate grain for storage in large vertical silos, the entire structure is called a grain elevator. Question: What are spiral screws used for?
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[A]: yes

[Q]: Sentence: Later hired by the university, the officers were originally brought in to quell unrest between students and city residents and curb destructive student behavior. Question: Why was the campus police established?
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[A]: yes

[Q]: Sentence: Punjabi is the provincial language of Punjab. Question: How is Punjabi written?
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[A]:
no