[Q]: Sentence: Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Question: What devices are used to observe insulated system heat loss?
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[A]: no

[Q]: Sentence: An invention is a solution to a specific technological problem, which may be a product or a process and generally has to fulfil three main requirements: it has to be new, not obvious and there needs to be an industrial applicability.:17 Question: An invention is a solution to what type of problem?
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[A]: yes

[Q]: Sentence: They do not obviously resemble a typical leafless cactus such as an Echinocactus. Question: What are areoles?
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[A]:
no