Pythagorean Proof of Curvature for a Ball with a Radius of 3959 Miles (Using AutoCAD 2015 with 15-Digit Precision)

Micheal Kanke figured the math and created the chart with Autocad and First Released it in July 2015 on Facebook.  It was shared and modified it into several versions and reshared virally.  

Earth Curvature AutoCAD Chart