[Q]: Sentence: Ignacy ukasiewicz improved Gesner's method to develop a means of refining kerosene from the more readily available "rock oil" ("petr-oleum") seeps in 1852 and the first rock oil mine was built in Bobrka, near Krosno in Galicia in the following year. Question: Who discovered the process of refining kerosene from coal?
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[A]: no

[Q]: Sentence: Several groups of extinct gymnosperms, in particular seed ferns, have been proposed as the ancestors of flowering plants, but there is no continuous fossil evidence showing exactly how flowers evolved. Question: What fossil evidence is lacking when it comes to flowers?
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[A]: yes

[Q]: Sentence: At least some Scythians seem to have become Hellenized, because we know of conflicts between the elites of the Scythian kingdom over the adoption of Greek ways. Question: From whom did the Scythians of Central Asia discover Hellenistic culture?
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[A]:
no