[Q]: Sentence: Some of these civilizations had long faded by the time of the first significant European and African arrivals (ca. Question: How do we know about some of the civilizations that were gone by the time of European arrival?
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[A]: no

[Q]: Sentence: Sometimes a piece of glacier will detach or break resulting in flooding, property damage and loss of life. Question: What causes flooding, property damage, and loss of life?
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[A]: yes

[Q]: Sentence: For example, at the time of the Voyager 2 flyby in 1989, the planet's southern hemisphere had a Great Dark Spot comparable to the Great Red Spot on Jupiter. Question: What weather feature does Neptune have stronger than any other planet?
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[A]:
no