9514 1404 393
Answer:
C. 168°
Explanation:
The exterior angle at any vertex of an n-gon will be ...
360°/n
So a 30-gon will have exterior angles of ...
360°/30 = 12°
The adjacent interior angle is supplementary to this, so is ...
180° -12° = 168°
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Using the reasonableness test
You know that the interior angles of a square are 90°, and that regular polygons with more sides have larger interior angles. The most any regular polygon's interior angle can be is 180°. The only answer choice between 90° and 180° is the correct choice: 168°.