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File:Vintage Hewlett-Packard Model 21 Electronic Pocket Calculator, Made in the U.S.A., A Scaled-Down HP 25, Circa 1975 (11574422413).jpg - Wikimedia Commons
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HP Slate 21-k100 Touchscreen All-in-One Desktop (Android 4.2 - upgradeable to 4.4) | Amazon price tracker / tracking, Amazon price history charts, Amazon price watches, Amazon price drop alerts | camelcamelcamel.com
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