My desire is that everything on this website (except in the store) shall remain free of obligatory cost to all who visit.
I am also determined that the site shall remain advertising free.
Please donate as you are able and in a manner that you think is reasonable for what you have been able to obtain from my work.
Thank you very much for your support!
Best teacher ever. You make math effortless.
Christopher C (on a CCM YouTube video demonstrating the Product Rule)
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