[Q]: Sentence: By then the language had developed a literary tradition, and since then it has changed little; journals from that period have no substantial differences from modern standard Czech, and contemporary Czechs can understand them with little difficulty. Question: Journals from the 18th century have no substantial differences from what?
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[A]: yes

[Q]: Sentence: Elemental hydrogen from solar, biological, or electrical sources require more energy to make it than is obtained by burning it, so in these cases hydrogen functions as an energy carrier, like a battery. Question: Where does the sun get its energy from?
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[A]: no

[Q]: Sentence: Near the northern Greek borders there are also some Slavicspeaking groups, locally known as Slavomacedonian-speaking, most of whose members identify ethnically as Greeks. Question: The Urums are known to speak what dialect?
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[A]:
no