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A chalkboard with the words upgrade thinking written on it. Board think structure, education.
Summary
An image of a chalkboard with the words upgrade thinking / A chalkboard with the words upgrade thinking written on it / Public domain stock illustration.
Tags
Date
2016
Source
pixabay.com
Copyright info
This image is from Pixabay and was published prior to July 2017 under the Creative Commons CC0 1.0 Universal Public Domain Dedication license https://web.archive.org/web/20161229043156/https://pixabay.com/en/service/terms/ . In July 2017, Pixabay switched the old sitewide license for all uploads from Creative Commons CC0 to a custom license arrangement that does not meet the Creative Commons CC0 1.0 Universal Public Domain Dedication license terms.
