Problem: A cappella:

The Swingle Singers used nonsense words to sound like instruments, but have been known to produce non-verbal versions of musical instruments. Like the other groups, examples of their music can be found on YouTube. Beatboxing, more accurately known as vocal percussion, is a technique used in a cappella music popularized by the hip-hop community, where rap is often performed a cappella also. The advent of vocal percussion added new dimensions to the a cappella genre and has become very prevalent in modern arrangements. Petra Haden used a four-track recorder to produce an a cappella version of The Who Sell Out including the instruments and fake advertisements on her album Petra Haden Sings: The Who Sell Out in 2005. Haden has also released a cappella versions of Journey's "Don't Stop Believin'", The Beach Boys' "God Only Knows" and Michael Jackson's "Thriller". In 2009, Toyota commissioned Haden to perform three songs for television commercials for the third-generation Toyota Prius, including an a cappella version of The Bellamy Brothers' 1970s song "Let Your Love Flow".[citation needed]

On what website can many a capella groups' music be listened to?
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A: YouTube


Problem: In 530 BC Cyrus the Great, King of the Persian Achaemenid Empire crossed the Hindu-Kush mountains to seek tribute from the tribes of Kamboja, Gandhara and the trans-India region (modern Afghanistan and Pakistan). By 520 BC, during the reign of Darius I of Persia, much of the northwestern subcontinent (present-day eastern Afghanistan and Pakistan) came under the rule of the Persian Achaemenid Empire, as part of the far easternmost territories. The area remained under Persian control for two centuries. During this time India supplied mercenaries to the Persian army then fighting in Greece.
What king ruled Persia in 520 BC?
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Answer: Darius I of Persia


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
From 1950 to 2011, world population increased from 2.5 billion to 7 billion and is forecast to reach a plateau of more than 9 billion during the 21st century. Sir David King, former chief scientific adviser to the UK government, told a parliamentary inquiry: "It is self-evident that the massive growth in the human population through the 20th century has had more impact on biodiversity than any other single factor." At least until the middle of the 21st century, worldwide losses of pristine biodiverse land will probably depend much on the worldwide human birth rate.
Who is the former chief scientific adviser to the UK government?
A: Sir David King


Context and question: The character of New York's large residential districts is often defined by the elegant brownstone rowhouses and townhouses and shabby tenements that were built during a period of rapid expansion from 1870 to 1930. In contrast, New York City also has neighborhoods that are less densely populated and feature free-standing dwellings. In neighborhoods such as Riverdale (in the Bronx), Ditmas Park (in Brooklyn), and Douglaston (in Queens), large single-family homes are common in various architectural styles such as Tudor Revival and Victorian.
In what borough is the Ditmas Park neighborhood located?
Answer: Brooklyn


Question: Players may only be transferred during transfer windows that are set by the Football Association. The two transfer windows run from the last day of the season to 31 August and from 31 December to 31 January. Player registrations cannot be exchanged outside these windows except under specific licence from the FA, usually on an emergency basis. As of the 2010–11 season, the Premier League introduced new rules mandating that each club must register a maximum 25-man squad of players aged over 21, with the squad list only allowed to be changed in transfer windows or in exceptional circumstances. This was to enable the 'home grown' rule to be enacted, whereby the League would also from 2010 require at least 8 of the named 25 man squad to be made up of 'home-grown players'.
Is there an answer to this question: In which season was it mandated that each club must have a maximum 21-man squad of players over 25?

Answer: unanswerable


Question: Managers in the Premier League are involved in the day-to-day running of the team, including the training, team selection, and player acquisition. Their influence varies from club-to-club and is related to the ownership of the club and the relationship of the manager with fans. Managers are required to have a UEFA Pro Licence which is the final coaching qualification available, and follows the completion of the UEFA 'B' and 'A' Licences. The UEFA Pro Licence is required by every person who wishes to manage a club in the Premier League on a permanent basis (i.e. more than 12 weeks – the amount of time an unqualified caretaker manager is allowed to take control). Caretaker appointments are managers that fill the gap between a managerial departure and a new appointment. Several caretaker managers have gone on to secure a permanent managerial post after performing well as a caretaker; examples include Paul Hart at Portsmouth and David Pleat at Tottenham Hotspur.
Is there an answer to this question: Is this licence required on a permanent basis?

Answer:
The UEFA Pro Licence is required by every person who wishes to manage a club in the Premier League on a permanent basis