Here is a question about this article: After the American Revolutionary War, the number and proportion of free people of color increased markedly in the North and the South as slaves were freed. Most northern states abolished slavery, sometimes, like New York, in programs of gradual emancipation that took more than two decades to be completed. The last slaves in New York were not freed until 1827. In connection with the Second Great Awakening, Quaker and Methodist preachers in the South urged slaveholders to free their slaves. Revolutionary ideals led many men to free their slaves, some by deed and others by will, so that from 1782 to 1810, the percentage of free people of color rose from less than one percent to nearly 10 percent of blacks in the South.
What is the answer to this question: How much did the percentage of free people in the South change from 1782 to 1810?
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So... the percentage of free people of color rose from less than one percent to nearly 10 percent of blacks in the South.

Here is a question about this article: In 1935, Reza Shah requested the international community to refer to the country by its native name, Iran. As the New York Times explained at the time, "At the suggestion of the Persian Legation in Berlin, the Tehran government, on the Persian New Year, Nowruz, March 21, 1935, substituted Iran for Persia as the official name of the country." Opposition to the name change led to the reversal of the decision, and Professor Ehsan Yarshater, editor of Encyclopdia Iranica, propagated a move to use Persia and Iran interchangeably. Today, both Persia and Iran are used in cultural contexts; although, Iran is the name used officially in political contexts.
What is the answer to this question: When did Reza Shan request that Iran officially be referred to as Iran and not Persia?
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So... 1935

Here is a question about this article: For an unprecedented eight consecutive years, from the 200304 television season through the 201011 season, either its performance or result show had been ranked number one in U.S. television ratings. The popularity of American Idol however declined, and on May 11, 2015, Fox announced that the series would conclude its run in its fifteenth season.
What is the answer to this question: How many consecutive years did American Idol been ranked number one in ratings?
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So...
eight