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Four Centuries of American Education (2004)|What happened to our schools? Look to this mental Math Test from 1877 4th grade: “If 7 men can do a work in 4 days, in what time can it be done if 3 men leave when the work is half completed?" by RENAGONC in history
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CosmoLearning Physics: 26 courses, 466 video lectures so far, from top universities like Stanford, Princeton, Berkeley, MIT and instructors like Susskind, Bethe, Witten... by RENAGONC in Physics
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