Problem: Old English:

Another source of loanwords was Old Norse, which came into contact with Old English via the Scandinavian rulers and settlers in the Danelaw from the late 9th century, and during the rule of Cnut and other Danish kings in the early 11th century. Many place-names in eastern and northern England are of Scandinavian origin. Norse borrowings are relatively rare in Old English literature, being mostly terms relating to government and administration. The literary standard, however, was based on the West Saxon dialect, away from the main area of Scandinavian influence; the impact of Norse may have been greater in the eastern and northern dialects. Certainly in Middle English texts, which are more often based on eastern dialects, a strong Norse influence becomes apparent. Modern English contains a great many, often everyday, words that were borrowed from Old Norse, and the grammatical simplification that occurred after the Old English period is also often attributed to Norse influence.

During what century did Cnut rule?
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A: 11th

Problem: Asphalt:

The first British patent for the use of asphalt/bitumen was 'Cassell's patent asphalte or bitumen' in 1834. Then on 25 November 1837, Richard Tappin Claridge patented the use of Seyssel asphalt (patent #7849), for use in asphalte pavement, having seen it employed in France and Belgium when visiting with Frederick Walter Simms, who worked with him on the introduction of asphalt to Britain. Dr T. Lamb Phipson writes that his father, Samuel Ryland Phipson, a friend of Claridge, was also "instrumental in introducing the asphalte pavement (in 1836)". Indeed, mastic pavements had been previously employed at Vauxhall by a competitor of Claridge, but without success.

The second patent, Cassell's patent, was issued in which year?
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A: unanswerable

Problem: Poultry:

Clay models of ducks found in China dating back to 4000 BC may indicate the domestication of ducks took place there during the Yangshao culture. Even if this is not the case, domestication of the duck took place in the Far East at least 1500 years earlier than in the West. Lucius Columella, writing in the first century BC, advised those who sought to rear ducks to collect wildfowl eggs and put them under a broody hen, because when raised in this way, the ducks "lay aside their wild nature and without hesitation breed when shut up in the bird pen". Despite this, ducks did not appear in agricultural texts in Western Europe until about 810 AD, when they began to be mentioned alongside geese, chickens, and peafowl as being used for rental payments made by tenants to landowners.

When did ducks begin to appear in the books of Western Europeon Society ?
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A: ducks did not appear in agricultural texts in Western Europe until about 810 AD

Problem: Classical music:

Given the wide range of styles in classical music, from Medieval plainchant sung by monks to Classical and Romantic symphonies for orchestra from the 1700s and 1800s to avant-garde atonal compositions for solo piano from the 1900s, it is difficult to list characteristics that can be attributed to all works of that type. However, there are characteristics that classical music contains that few or no other genres of music contain, such as the use of a printed score and the performance of very complex instrumental works (e.g., the fugue). As well, although the symphony did not exist through the entire classical music period, from the mid-1700s to the 2000s the symphony ensembleand the works written for ithave become a defining feature of classical music.

What did not exist through the entire classical music period?
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A:
the symphony