IIC test does not explicitly test plane geometry. There
are no questions that exclusively ask about polygons or angles.
But don’t get too psyched, because you still need to have the subject
down cold. The writers of the Math IIC incorporate various aspects
of plane geometry into questions covering 3-D geometry, coordinate geometry,
and trigonometry. In all, about 40 percent of the questions on the
Math IIC involve plane geometry in some way.