Find a formula for the fourth degree polynomial p(x) whose graph is symetric about the y-axis, and which has a y-intercept of 0, and a global maximum at (2,16) and (-2,16)

The pyraminx is a rubik's cube-type toy in the shape of a tetrahedron. the pyraminx shown below has edges 15\,\text{cm}15cm long and vertical height h=12.2\,\text{cm}h=12.2cm. the triangle drawn with dashed lines is a right triangle. what is the distance rr? round your answer to the nearest tenth.