[Q]: Sentence: Construction may be less robust than in commercial designs with shorter maintenance periods, but safety systems such as locks on shaft access doors, fall arrestors, and emergency phones must still be present in the event of malfunction. Question: What type of elevators are generally less costly than full commercial elevators?
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[A]: no

[Q]: Sentence: A survey is being conducted to extend this railway line to Kangra (via Nadaun). Question: What is being conducted to extend the railway?
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[A]: yes

[Q]: Sentence: One of the central problems in the anthropology of art concerns the universality of 'art' as a cultural phenomenon. Question: When was Art as Cultural System penned?
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[A]:
no