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vacuum tube:vacuum tube: see electron tube. The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2007, Columbia University Press. All rights reserved. More on vacuum tube from Fact Monster:
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Part of Family Education Network | Homework Help | Reference Site | K-8 Kids | Poptropica | Parenting Advice | Teacher Resources | Online Gradebook
© 2000–2012 Pearson Education, publishing as Fact Monster™
