Update to the Big Font Math Reference

Original post:  https://edspi31415.blogspot.com/2018/04/april-11-2018-seven-years.html

I added several sections to the Big Math Reference document, which you can download on the right side of the blog.

What is added:

* Days Between Dates Algorithm
*  Astronomy Formulas: Kepler's 3rd Law, Parallax, Luminosity, Schwartzchild Radius
*  Physics:  Projectile Motion, Linear Motion, Angular Motion
*  Electronics:  Ohm's Law, Resistance

Eddie