The problem: Answer a question about this article:
During the years 1940-1955, the rate of decline in the U.S. death rate accelerated from 2% per year to 8% per year, then returned to the historical rate of 2% per year. The dramatic decline in the immediate post-war years has been attributed to the rapid development of new treatments and vaccines for infectious disease that occurred during these years. Vaccine development continued to accelerate, with the most notable achievement of the period being Jonas Salk's 1954 development of the polio vaccine under the funding of the non-profit National Foundation for Infantile Paralysis. The vaccine process was never patented, but was instead given to pharmaceutical companies to manufacture as a low-cost generic. In 1960 Maurice Hilleman of Merck Sharp & Dohme identified the SV40 virus, which was later shown to cause tumors in many mammalian species. It was later determined that SV40 was present as a contaminant in polio vaccine lots that had been administered to 90% of the children in the United States. The contamination appears to have originated both in the original cell stock and in monkey tissue used for production. In 2004 the United States Cancer Institute announced that it had concluded that SV40 is not associated with cancer in people.
What virus caused tumors in most mammals?
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The answer: SV40

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Other types of lossy compressors, such as the linear predictive coding (LPC) used with speech, are source-based coders. These coders use a model of the sound's generator (such as the human vocal tract with LPC) to whiten the audio signal (i.e., flatten its spectrum) before quantization. LPC may be thought of as a basic perceptual coding technique: reconstruction of an audio signal using a linear predictor shapes the coder's quantization noise into the spectrum of the target signal, partially masking it.
What uses a model of the sound's generator?
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The answer: source-based coders

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While slaveholding was slightly less concentrated than in some Southern states, according to the 1860 census, more than 330,000 people, or 33% of the population of 992,622, were enslaved African Americans. They lived and worked chiefly on plantations in the eastern Tidewater. In addition, 30,463 free people of color lived in the state. They were also concentrated in the eastern coastal plain, especially at port cities such as Wilmington and New Bern, where a variety of jobs were available. Free African Americans were allowed to vote until 1835, when the state revoked their suffrage in restrictions following the slave rebellion of 1831 led by Nat Turner. Southern slave codes criminalized willful killing of a slave in most cases.
Where were most of the slaves in North Carolina located?
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The answer: eastern Tidewater

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Most historical accounts state that the island was discovered on 21 May 1502 by the Galician navigator Joao da Nova sailing at the service of Portugal, and that he named it "Santa Helena" after Helena of Constantinople. Another theory holds that the island found by da Nova was actually Tristan da Cunha, 2,430 kilometres (1,510 mi) to the south, and that Saint Helena was discovered by some of the ships attached to the squadron of Estevao da Gama expedition on 30 July 1503 (as reported in the account of clerk Thome Lopes). However, a paper published in 2015 reviewed the discovery date and dismissed the 18 August as too late for da Nova to make a discovery and then return to Lisbon by 11 September 1502, whether he sailed from St Helena or Tristan da Cunha. It demonstrates the 21 May is probably a Protestant rather than Catholic or Orthodox feast-day, first quoted in 1596 by Jan Huyghen van Linschoten, who was probably mistaken because the island was discovered several decades before the Reformation and start of Protestantism. The alternative discovery date of 3 May, the Catholic feast-day for the finding of the True Cross by Saint Helena in Jerusalem, quoted by Odoardo Duarte Lopes and Sir Thomas Herbert is suggested as being historically more credible.
What person is Saint Helena Island named after?
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The answer:
Helena of Constantinople