Problem: The Xingu River is in which South American country?
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A: brazil

Problem: In what country are/were violent demonstrations in 2011 against President Hosni Mubarak and his 30-year leadership?
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A: egypt

Problem: Reginald Doherty, Arthur Gore and Fred Perry are associated with which sport?
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A: tennis

Problem: In Greek mythology, Artemis is the twin sister of which god?
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A:
apollo