Contained herein: Method for finding the height and center of an equilateral triangle and a tetrahedron in terms of side length. Two methods to find the angle formed by the center and any two vertices, AKA the tetrahedral angle. A python program for calculating the above. How to make a paper tetrahedron.
There is a growing movement in certain math circles towards the opinion that π (pi) is wrong. Which is to say, it is the wrong number to be using and we would be better off using a symbol which means 2π, with the current candidate being τ (tau). Don't let this boring abstract put you to sleep; there are fun, informative videos within. Go watch them prove quite handily that π is a problem.