Problem: Which glassy, dark volcanic rock was used by some to make edged tools and arrowheads?
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A: obsidian

Problem: "Who had a UK No.1 album, in 2002, with ""Escapology""?"
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A: robbie williams

Problem: What appropriately named spacecraft launched in 1972 has become the first artificial object to leave the Solar System?
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A: pioneer 10

Problem: "The Hector Berlioz opera ""Les Troyens"" is based on a poem written by whom?"
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A:
virgil