What is the measure of an exterior angle of a regular decagon (10-sided polygon)?
Answer: B
The sum of the exterior angles of any convex polygon is always 360°.
For a regular n-sided polygon, each exterior angle has the same measure.
Measure of one exterior angle = 360° / n.
For a decagon, n=10.
Exterior angle = 360° / 10 = 36°.