Understanding map projections is an important map-reading skill. Features graphics and links to examples of many different projections and an activity on making a Mercator projection.

An advanced explanation of the valence shell electron pair repulsion (VSEPR) theory describes specific molecular models involving digonal, trigonal, tetrahedral, and octahedral coordination, as well as central atoms with five bonds....

Given a figure on the coordinate plane and a center of a rotation, find the angle for the rotation that maps one figure to the other.