[Q]: Sentence: The period that followed is known traditionally as the Era of Fragmentation, when political control over Tibet became divided between regional warlords and tribes with no dominant centralized authority. Question: What followed the collapse of imperial Tibet?
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[A]: yes

[Q]: Sentence: He announced his resignation on television later that day, and ceded all presidential powers to his then-Vice President Zakaria Mohieddin, who had no prior information of this decision and refused to accept the post. Question: Who rejected Nasser's offer to become the new president?
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[A]: yes

[Q]: Sentence: In 1853 a stagecoach bus line was established joining Montevideo with the newly formed settlement of Union and the first natural gas street lights were inaugurated.[citation needed] Question: Between what years were the first natural gas street lights constructed?
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[A]:
no