Problem: American Idol:

David Archuleta's performance of John Lennon's "Imagine" was considered by many as one of the best of the season. Jennifer Lopez, who was brought in as a judge in season ten, called it a beautiful song-moment that she will never forget. Jason Castro's semi-final performance of "Hallelujah" also received considerable attention, and it propelled Jeff Buckley's version of the song to the top of the Billboard digital song chart. This was the first season in which contestants' recordings were released onto iTunes after their performances, and although sales information was not released so as not to prejudice the contest, leaked information indicated that contestants' songs frequently reached the top of iTunes sales charts.

On what digital platform were contestants performances released to after airing on American Idol?
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A: iTunes


Problem: Late Middle Ages:

As the European population was severely reduced, land became more plentiful for the survivors, and labour consequently more expensive. Attempts by landowners to forcibly reduce wages, such as the English 1351 Statute of Laborers, were doomed to fail. These efforts resulted in nothing more than fostering resentment among the peasantry, leading to rebellions such as the French Jacquerie in 1358 and the English Peasants' Revolt in 1381. The long-term effect was the virtual end of serfdom in Western Europe. In Eastern Europe, on the other hand, landowners were able to exploit the situation to force the peasantry into even more repressive bondage.

Which economic system was ultimately started by the upheavals of the 14th century?
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A: unanswerable


Problem: Royal assent:

Measures, which were the means by which the National Assembly for Wales passed legislation between 2006 and 2011, were assented to by the Queen by means of an Order in Council. Section 102 of the Government of Wales Act 2006 required the Clerk to the Assembly to present measures passed by the assembly after a four-week period during which the Counsel General for Wales or the Attorney General could refer the proposed measure to the Supreme Court for a decision as to whether the measure was within the assembly's legislative competence.

What were "measures" in Wales?
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A: the means by which the National Assembly for Wales passed legislation between 2006 and 2011


Problem: Hard rock:

With the rise of disco in the US and punk rock in the UK, hard rock's mainstream dominance was rivalled toward the later part of the decade. Disco appealed to a more diverse group of people and punk seemed to take over the rebellious role that hard rock once held. Early punk bands like The Ramones explicitly rebelled against the drum solos and extended guitar solos that characterised stadium rock, with almost all of their songs clocking in around two minutes with no guitar solos. However, new rock acts continued to emerge and record sales remained high into the 1980s. 1977 saw the début and rise to stardom of Foreigner, who went on to release several platinum albums through to the mid-1980s. Midwestern groups like Kansas, REO Speedwagon and Styx helped further cement heavy rock in the Midwest as a form of stadium rock. In 1978, Van Halen emerged from the Los Angeles music scene with a sound based around the skills of lead guitarist Eddie Van Halen. He popularised a guitar-playing technique of two-handed hammer-ons and pull-offs called tapping, showcased on the song "Eruption" from the album Van Halen, which was highly influential in re-establishing hard rock as a popular genre after the punk and disco explosion, while also redefining and elevating the role of electric guitar.

Which Van Halen instrumental showcased the guitar mastery of Eddie Van Halen?
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A:
"Eruption"