Problem: Gramophone record:

Through the 1960s, 1970s, and 1980s, various methods to improve the dynamic range of mass-produced records involved highly advanced disc cutting equipment. These techniques, marketed, to name two, as the CBS DisComputer and Teldec Direct Metal Mastering, were used to reduce inner-groove distortion. RCA Victor introduced another system to reduce dynamic range and achieve a groove with less surface noise under the commercial name of Dynagroove. Two main elements were combined: another disk material with less surface noise in the groove and dynamic compression for masking background noise. Sometimes this was called "diaphragming" the source material and not favoured by some music lovers for its unnatural side effects. Both elements were reflected in the brandname of Dynagroove, described elsewhere in more detail. It also used the earlier advanced method of forward-looking control on groove spacing with respect to volume of sound and position on the disk. Lower recorded volume used closer spacing; higher recorded volume used wider spacing, especially with lower frequencies. Also, the higher track density at lower volumes enabled disk recordings to end farther away from the disk center than usual, helping to reduce endtrack distortion even further.

What technique were used to reduce inner-groove distortion?
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A: CBS DisComputer and Teldec Direct Metal Mastering

Problem: Strasbourg:

Strasbourg features a number of prominent parks, of which several are of cultural and historical interest: the Parc de l'Orangerie, laid out as a French garden by Andre le Notre and remodeled as an English garden on behalf of Josephine de Beauharnais, now displaying noteworthy French gardens, a neo-classical castle and a small zoo; the Parc de la Citadelle, built around impressive remains of the 17th-century fortress erected close to the Rhine by Vauban; the Parc de Pourtales, laid out in English style around a baroque castle (heavily restored in the 19th century) that now houses a small three-star hotel, and featuring an open-air museum of international contemporary sculpture. The Jardin botanique de l'Universite de Strasbourg (botanical garden) was created under the German administration next to the Observatory of Strasbourg, built in 1881, and still owns some greenhouses of those times. The Parc des Contades, although the oldest park of the city, was completely remodeled after World War II. The futuristic Parc des Poteries is an example of European park-conception in the late 1990s. The Jardin des deux Rives, spread over Strasbourg and Kehl on both sides of the Rhine opened in 2004 and is the most extended (60-hectare) park of the agglomeration. The most recent park is Parc du Heyritz (8,7 ha), opened in 2014 along a canal facing the hopital civil.

In what year was the Parc de Pourtales laid out?
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A: unanswerable

Problem: Red:

But, like many colors, it also had a negative association, with heat, destruction and evil. A prayer to god Isis said: "Oh Isis, protect me from all things evil and red." The ancient Egyptians began manufacturing pigments in about 4000 BC. Red ochre was widely used as a pigment for wall paintings, particularly as the skin color of men. An ivory painter's palette found inside the tomb of King Tutankhamun had small compartments with pigments of red ochre and five other colors. The Egyptians used the root of the rubia, or madder plant, to make a dye, later known as alizarin, and also used it to color white power to use as a pigment, which became known as madder lake, alizarin or alizarin crimson.

Who used the white alizarin to make crimson pigment?
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A: unanswerable

Problem: MP3:

The psychoacoustic masking codec was first proposed in 1979, apparently independently, by Manfred R. Schroeder, et al. from Bell Telephone Laboratories, Inc. in Murray Hill, NJ, and M. A. Krasner both in the United States. Krasner was the first to publish and to produce hardware for speech (not usable as music bit compression), but the publication of his results as a relatively obscure Lincoln Laboratory Technical Report did not immediately influence the mainstream of psychoacoustic codec development. Manfred Schroeder was already a well-known and revered figure in the worldwide community of acoustical and electrical engineers, but his paper was not much noticed, since it described negative results due to the particular nature of speech and the linear predictive coding (LPC) gain present in speech. Both Krasner and Schroeder built upon the work performed by Eberhard F. Zwicker in the areas of tuning and masking of critical bands, that in turn built on the fundamental research in the area from Bell Labs of Harvey Fletcher and his collaborators. A wide variety of (mostly perceptual) audio compression algorithms were reported in IEEE's refereed Journal on Selected Areas in Communications. That journal reported in February 1988 on a wide range of established, working audio bit compression technologies, some of them using auditory masking as part of their fundamental design, and several showing real-time hardware implementations.

What does LPC stand for?
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A:
linear predictive coding