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Atlapedia - This online atlas offers information on every country in the world, and includes facts and figures on geography, climate, religion, population, language, economy, history, and more. A maps section provides full-color physical and political maps of world regions. You can submit a question or look in the files of previously asked questions. Different categories group questions into age levels, from basic counting in Kindergarten through trigonometry in college. You can submit a question to the experts at Scientific American, or browse through nine areas of science, including chemistry, biology, and astronomy.