Final answer:
The measure of an exterior angle of a regular octagon is 45°.
Step-by-step explanation:
The measure of an exterior angle of a regular octagon can be found by using the formula: 360° divided by the number of sides in the polygon. As an octagon has 8 sides, the measure of an exterior angle of a regular octagon is 360° divided by 8, which is 45°.
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