Problem: In 1915 which Dutch engineer perfected the interrupter, which allowed a machine gun to fire safely through the propellers of an aircraft?
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A: fokker

Problem: Which surname is shared by an American Jazz Singer and an American author ? ( It was also the middle name of an American president.)
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A: fitzgerald

Problem: Edward Fairfax Rochester is a character in which 19th century novel?
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A: jane eyre

Problem: The towns of Bishop's Stortford and Berkhamsted are in which English county?
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A:
hertfordshire