Problem: Greece:

During the 19th and 20th centuries there was a major dispute known as the Greek language question, on whether the official language of Greece should be the archaic Katharevousa, created in the 19th century and used as the state and scholarly language, or the Dimotiki, the form of the Greek language which evolved naturally from Byzantine Greek and was the language of the people. The dispute was finally resolved in 1976, when Dimotiki was made the only official variation of the Greek language, and Katharevousa fell to disuse.

When was the Greek language Katharevousa created?
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A: the 19th century


Problem: Neptune:

In 1821, Alexis Bouvard published astronomical tables of the orbit of Neptune's neighbour Uranus. Subsequent observations revealed substantial deviations from the tables, leading Bouvard to hypothesise that an unknown body was perturbing the orbit through gravitational interaction. In 1843, John Couch Adams began work on the orbit of Uranus using the data he had. Via Cambridge Observatory director James Challis, he requested extra data from Sir George Airy, the Astronomer Royal, who supplied it in February 1844. Adams continued to work in 1845–46 and produced several different estimates of a new planet.

What happened in 1831?
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A: unanswerable


Problem: Hard rock:

Hard rock is a form of loud, aggressive rock music. The electric guitar is often emphasised, used with distortion and other effects, both as a rhythm instrument using repetitive riffs with a varying degree of complexity, and as a solo lead instrument. Drumming characteristically focuses on driving rhythms, strong bass drum and a backbeat on snare, sometimes using cymbals for emphasis. The bass guitar works in conjunction with the drums, occasionally playing riffs, but usually providing a backing for the rhythm and lead guitars. Vocals are often growling, raspy, or involve screaming or wailing, sometimes in a high range, or even falsetto voice.

What is played to keep the music from becoming repetitive?
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A: unanswerable


Problem: Orthodox Judaism:

Although sizable Orthodox Jewish communities are located throughout the United States, many American Orthodox Jews live in New York State, particularly in the New York City Metropolitan Area. Two of the main Orthodox communities in the United States are located in New York City and Rockland County. In New York City, the neighborhoods of Borough Park, Midwood, Williamsburg, and Crown Heights, located in the borough of Brooklyn, have particularly large Orthodox communities. The most rapidly growing community of American Orthodox Jews is located in Rockland County and the Hudson Valley of New York, including the communities of Monsey, Monroe, New Square, and Kiryas Joel. There are also sizable and rapidly growing Orthodox communities throughout New Jersey, particularly in Lakewood, Teaneck, Englewood, Passaic, and Fair Lawn.

What area besides New York are the Orthodox communities in decline?
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A:
unanswerable