Problem: Web browser:

The first web browser was invented in 1990 by Sir Tim Berners-Lee. Berners-Lee is the director of the World Wide Web Consortium (W3C), which oversees the Web's continued development, and is also the founder of the World Wide Web Foundation. His browser was called WorldWideWeb and later renamed Nexus.

What did Nexus invent in 1990?
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A: unanswerable


Problem: Kievan Rus%27:

The change in political structure led to the inevitable development of the peasant class or smerdy. The smerdy were free un-landed people that found work by labouring for wages on the manors which began to develop around 1031 as the verv' began to dominate socio-political structure. The smerdy were initially given equality in the Kievian law code, they were theoretically equal to the prince, so they enjoyed as much freedom as can be expected of manual labourers. However, in the 13th century they began to slowly lose their rights and became less equal in the eyes of the law.

Who began to slowly gain their rights and become more equal in the eyes of the law?
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A: unanswerable


Problem: Quran:

In 2015, fragments of a very early Quran, dating back to 1370 years ago, were discovered in the library of the University of Birmingham, England. According to the tests carried out by Oxford University Radiocarbon Accelerator Unit, "with a probability of more than 95%, the parchment was from between 568 and 645". The manuscript is written in Hijazi script, an early form of written Arabic. This is possibly the earliest extant exemplar of the Quran, but as the tests allow a range of possible dates, it cannot be said with certainty which of the existing versions is the oldest. Saudi scholar Saud al-Sarhan has expressed doubt over the age of the fragments as they contain dots and chapter separators that are believed to have originated later.

What feature of the Birmingham Quran fragments' text make some doubt that it is older than other known versions of the Quran?
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A: dots and chapter separators


Problem: Association football:

At a professional level, most matches produce only a few goals. For example, the 2005–06 season of the English Premier League produced an average of 2.48 goals per match. The Laws of the Game do not specify any player positions other than goalkeeper, but a number of specialised roles have evolved. Broadly, these include three main categories: strikers, or forwards, whose main task is to score goals; defenders, who specialise in preventing their opponents from scoring; and midfielders, who dispossess the opposition and keep possession of the ball to pass it to the forwards on their team. Players in these positions are referred to as outfield players, to distinguish them from the goalkeeper. These positions are further subdivided according to the area of the field in which the player spends most time. For example, there are central defenders, and left and right midfielders. The ten outfield players may be arranged in any combination. The number of players in each position determines the style of the team's play; more forwards and fewer defenders creates a more aggressive and offensive-minded game, while the reverse creates a slower, more defensive style of play. While players typically spend most of the game in a specific position, there are few restrictions on player movement, and players can switch positions at any time. The layout of a team's players is known as a formation. Defining the team's formation and tactics is usually the prerogative of the team's manager.

Who's job is to prevent their team from scoring?
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A:
unanswerable