Answer:
12°
Step-by-step explanation:
So, for your 30-gon, the interior angles total up to (30-2) * 180 = 5040. Each interior angle is that total divided by the number of interior angles, or 5040/30 = 168º:
The measure of each exterior angle is the total divided by the number of angles, or 360/30 = 12º.
