[Q]: Sentence: South America became linked to North America through the Isthmus of Panama during the Pliocene, bringing a nearly complete end to South America's distinctive marsupial faunas. Question: What period came after the Pliocene?
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[A]: no

[Q]: Sentence: On 23 June 1757, the English East India Company defeated Siraj-ud-Daula, the Nawab of Bengal, in the Battle of Plassey. Question: When did the English East India Company defeat Siraj-ud-Daula?
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[A]: yes

[Q]: Sentence: This may be modified by adding low-density materials such as boron, which lowers the index of refraction (see crown glass), or increased (to as much as 1.8) with high-density materials such as (classically) lead oxide (see flint glass and lead glass), or in modern uses, less toxic oxides of zirconium, titanium, or barium. Question: What can be used to make glass less refractive?
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[A]:
yes