1. what is the sum of the interior angles of an isosceles triangle? a. 90° b. 180° c. 270° d. 360°


2. what is the sum of the interior angles of a regular undecagon? a. 1620° b.1260°
c. 147° d. 33°

3. find the measure of one interior angle of a regular polygon with 20 sides.

a. 3240° b. 18° c. 126° c. 162°

4. what is the measure of an exteriorangle of an 18-sided polygon? a. 10° b. 20° c. 30° d. 40°

5. if the sum of the enterior angles of a polygon is 2520°, then the measure of one exterior angle is ____

a. 19.5° b. 20.5° c. 21.5°

d. 22.5°
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