Problem: What London attraction features on the 2009 commemorative British 50p coin?
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A: kew gardens

Problem: What substance was once used to make billiard balls and piano keys?
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A: ivory

Problem: What is the official residence of the French President?
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A: elysee palace

Problem: Gemini Force One is a 21st century extension of what secretive organization?
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A:
thunderbirds