A regular polygon has an interior angle of 150°. How many sides does it have?
Answer: C
If the interior angle is 150°, the exterior angle is 180° - 150° = 30°.
The number of sides 'n' of a regular polygon is given by n = 360° / (exterior angle).
n = 360° / 30° = 12.
The polygon has 12 sides (a dodecagon).