Problem: Infrared:

Infrared is used in night vision equipment when there is insufficient visible light to see. Night vision devices operate through a process involving the conversion of ambient light photons into electrons that are then amplified by a chemical and electrical process and then converted back into visible light. Infrared light sources can be used to augment the available ambient light for conversion by night vision devices, increasing in-the-dark visibility without actually using a visible light source.

What equipment uses the infrared spectrum with visible light?
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A: unanswerable

Problem: Universal Studios:

Despite Laemmle's role as an innovator, he was an extremely cautious studio chief. Unlike rivals Adolph Zukor, William Fox, and Marcus Loew, Laemmle chose not to develop a theater chain. He also financed all of his own films, refusing to take on debt. This policy nearly bankrupted the studio when actor-director Erich von Stroheim insisted on excessively lavish production values for his films Blind Husbands (1919) and Foolish Wives (1922), but Universal shrewdly gained a return on some of the expenditure by launching a sensational ad campaign that attracted moviegoers. Character actor Lon Chaney became a drawing card for Universal in the 1920s, appearing steadily in dramas. His two biggest hits for Universal were The Hunchback of Notre Dame (1923) and The Phantom of the Opera (1925). During this period Laemmle entrusted most of the production policy decisions to Irving Thalberg. Thalberg had been Laemmle's personal secretary, and Laemmle was impressed by his cogent observations of how efficiently the studio could be operated. Promoted to studio chief, Thalberg was giving Universal's product a touch of class, but MGM's head of production Louis B. Mayer lured Thalberg away from Universal with a promise of better pay. Without his guidance Universal became a second-tier studio, and would remain so for several decades.

Who directed Blind Husbands?
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A: Erich von Stroheim

Problem: Steven Spielberg:

In 1987, as China began opening to Western capital investment, Spielberg shot the first American film in Shanghai since the 1930s, an adaptation of J. G. Ballard's autobiographical novel Empire of the Sun, starring John Malkovich and a young Christian Bale. The film garnered much praise from critics and was nominated for several Oscars, but did not yield substantial box office revenues. Reviewer Andrew Sarris called it the best film of the year and later included it among the best films of the decade. Spielberg was also a co-producer of the 1987 film *batteries not included.

Until the 1980s, when had an American film last been shot in Shanghai?
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A: the 1930s

Problem: Mandolin:

On the island of Crete, along with the lyra and the laouto (lute), the mandolin is one of the main instruments used in Cretan Music. It appeared on Crete around the time of the Venetian rule of the island. Different variants of the mandolin, such as the "mantola," were used to accompany the lyra, the violin, and the laouto. Stelios Foustalierakis reported that the mandolin and the mpoulgari were used to accompany the lyra in the beginning of the 20th century in the city of Rethimno. There are also reports that the mandolin was mostly a woman's musical instrument. Nowadays it is played mainly as a solo instrument in personal and family events on the Ionian islands and Crete.

What was one of the variants of the mandolin that was never used?
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A:
unanswerable