Problem: Law of the United States:

As federal judge Alex Kozinski has pointed out, binding precedent as we know it today simply did not exist at the time the Constitution was framed. Judicial decisions were not consistently, accurately, and faithfully reported on both sides of the Atlantic (reporters often simply rewrote or failed to publish decisions which they disliked), and the United Kingdom lacked a coherent court hierarchy prior to the end of the 19th century. Furthermore, English judges in the eighteenth century subscribed to now-obsolete natural law theories of law, by which law was believed to have an existence independent of what individual judges said. Judges saw themselves as merely declaring the law which had always theoretically existed, and not as making the law. Therefore, a judge could reject another judge's opinion as simply an incorrect statement of the law, in the way that scientists regularly reject each other's conclusions as incorrect statements of the laws of science.

What did the the UK courts in the end of the 19th century?
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A: unanswerable

Problem: Han dynasty:

The Xiongnu, a nomadic steppe confederation, defeated the Han in 200 BC and forced the Han to submit as a de facto inferior partner, but continued their raids on the Han borders. Emperor Wu of Han (r. 14187 BC) launched several military campaigns against them. The ultimate Han victory in these wars eventually forced the Xiongnu to accept vassal status as Han tributaries. These campaigns expanded Han sovereignty into the Tarim Basin of Central Asia, divided the Xiongnu into two separate confederations, and helped establish the vast trade network known as the Silk Road, which reached as far as the Mediterranean world. The territories north of Han's borders were quickly overrun by the nomadic Xianbei confederation. Emperor Wu also launched successful military expeditions in the south, annexing Nanyue in 111 BC and Dian in 109 BC, and in the Korean Peninsula where the Xuantu and Lelang Commanderies were established in 108 BC.

Which confederation defeated the Han in 200 BC?
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A: The Xiongnu

Problem: House music:

Soul and disco influenced house music, plus mixing and editing techniques earlier explored by disco, garage music and post-disco DJs, producers, and audio engineers such as Walter Gibbons, Tom Moulton, Jim Burgess, Larry Levan, Ron Hardy, M & M, and others who produced longer, more repetitive, and percussive arrangements of existing disco recordings. Early house producers such as Frankie Knuckles created similar compositions from scratch, using samplers, synthesizers, sequencers, and drum machines.

Who produced longer arrangements of drum recordings?
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A: unanswerable

Problem: London:

Within London, both the City of London and the City of Westminster have city status and both the City of London and the remainder of Greater London are counties for the purposes of lieutenancies. The area of Greater London has incorporated areas that were once part of the historic counties of Middlesex, Kent, Surrey, Essex and Hertfordshire. London's status as the capital of England, and later the United Kingdom, has never been granted or confirmed officiallyby statute or in written form.[note 6]

What areas within Greater London have city status?
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A:
the City of London and the City of Westminster