Problem: Which South American country has borders with all other South American countries apart from Ecuador and Chile?
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A: brazil

Problem: When a jeweler refers to a diamond's "cut," he is describing what aspect of the gem?
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A: shape

Problem: In 2013 Yahoo purchased which pictures and video microblogging website business that was founded in 2007 in New York City by David Karp?
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A: tumblr

Problem: In Greek myth, which three-headed dog guarded the gate to Hades?
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A:
cerberus