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Casio FX-260SLRSC Scientific and Engineering Calculator for $9.99 Shipped

Casio FX-260SLRSC Scientific and Engineering Calculator for $9.99 shipped.  Here is a screenshot for your reference.  It is solar-powered with internal battery back-up, and features 144 science mathe functions, a 10-digit + 2 exponent LCD screen, 1-variable statistics and standard deviations, and more.  Most places have it for about $15.