Exercise 24 Page 567

Consider the given regular polygon. If we connect each of the six vertices with the center, we create 6 congruent angles.

Knowing that a full turn is 360^(∘), we can calculate the measure of each angle. 360^(∘)/6=60^(∘) Therefore, a 60^(∘) rotation about the center maps the polygon onto itself.

The same is true if we rotate the polygon 120^(∘).

A rotation of 180^(∘) about the center will also work.

These measures correspond to choices C, F, and H.