Problem: After Germany invaded the Soviet Union on 22 June 1941, the Wehrmacht crossed the Estonian southern border on 7 July. The Red Army retreated behind the Parnu River Emajogi line on 12 July. At the end of July the Germans resumed their advance in Estonia working in tandem with the Estonian Forest Brothers. Both German troops and Estonian partisans took Narva on 17 August and the Estonian capital Tallinn on 28 August. After the Soviets were driven out from Estonia, German troops disarmed all the partisan groups.
Who helped the Germans take over Estonia?
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Answer: the Estonian Forest Brothers

Problem: Various American Idol alumni had success on various record charts around the world; in the U.S. they had achieved 345 number ones on the Billboard charts in its first ten years. According to Fred Bronson, author of books on the Billboard charts, no other entity has ever created as many hit-making artists and best-selling albums and singles. In 2007, American Idol alums accounted for 2.1% of all music sales. Its alumni have a massive impact on radio; in 2007, American Idol had become "a dominant force in radio" according to the president of the research company Mediabase which monitors radio stations Rich Meyer. By 2010, four winners each had more than a million radio spins, with Kelly Clarkson leading the field with over four million spins.
Who was the most successful American Idol winner on radio as of 2010?
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Answer: Kelly Clarkson

Problem: Jonassohn and Bjornson postulate that the major reason why no single generally accepted genocide definition has emerged is because academics have adjusted their focus to emphasise different periods and have found it expedient to use slightly different definitions to help them interpret events. For example, Frank Chalk and Kurt Jonassohn studied the whole of human history, while Leo Kuper and R. J. Rummel in their more recent works concentrated on the 20th century, and Helen Fein, Barbara Harff and Ted Gurr have looked at post World War II events. Jonassohn and Bjornson are critical of some of these studies, arguing that they are too expansive, and conclude that the academic discipline of genocide studies is too young to have a canon of work on which to build an academic paradigm.
What writer joined Jonassohn in the study of definitions?
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Answer:
unanswerable