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04:31 Civics The fight for the right to vote in the United States Lesson duration 04:31 782,769 Views
03:48 Physical Science The strengths and weaknesses of acids and bases Lesson duration 03:48 1,040,680 Views
04:08 Performing Arts The science of stage fright (and how to overcome it) Lesson duration 04:08 1,630,703 Views
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03:57 Literature & Language Speech acts: Constative and performative Lesson duration 03:57 210,704 Views