Here is a question about this article: The area near the border with Cameroon close to the coast is rich rainforest and part of the Cross-Sanaga-Bioko coastal forests ecoregion, an important centre for biodiversity. It is habitat for the drill monkey, which is found in the wild only in this area and across the border in Cameroon. The areas surrounding Calabar, Cross River State, also in this forest, are believed to contain the world's largest diversity of butterflies. The area of southern Nigeria between the Niger and the Cross Rivers has lost most of its forest because of development and harvesting by increased population, with it being replaced by grassland (see Cross-Niger transition forests).
What is the answer to this question: Why is southern Nigeria losing its forests?
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So... development and harvesting by increased population

Here is a question about this article: The U.S. recession that began in December 2007 ended in June 2009, according to the U.S. National Bureau of Economic Research (NBER) and the financial crisis appears to have ended about the same time. In April 2009 TIME magazine declared "More Quickly Than It Began, The Banking Crisis Is Over." The United States Financial Crisis Inquiry Commission dates the crisis to 2008. President Barack Obama declared on January 27, 2010, "the markets are now stabilized, and we've recovered most of the money we spent on the banks."
What is the answer to this question: On what date did President Barack Obama declare that the markets are stabilized?
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So... January 27, 2010

Here is a question about this article: By 1353, the three original cantons had joined with the cantons of Glarus and Zug and the Lucerne, Zurich and Bern city states to form the "Old Confederacy" of eight states that existed until the end of the 15th century. The expansion led to increased power and wealth for the federation. By 1460, the confederates controlled most of the territory south and west of the Rhine to the Alps and the Jura mountains, particularly after victories against the Habsburgs (Battle of Sempach, Battle of Nafels), over Charles the Bold of Burgundy during the 1470s, and the success of the Swiss mercenaries. The Swiss victory in the Swabian War against the Swabian League of Emperor Maximilian I in 1499 amounted to de facto independence within the Holy Roman Empire.
What is the answer to this question: Which century did the Old Confederacy of the eight states exist until?
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So...
end of the 15th century