Question

1. the sum of the interior angle measures of a convex dodecagon.

2. the measure of each interior angle of a regular 20-gon

Answer 1

dodecagon --- 12 sides

It must be regualar, that is, all sides must be equal and all 12 interior angles are equal.

sum = 180(n-2)
so each angle = 180(n-2)/n

for 12 sides:
each angle = 180(12-2)/12 = 150°

you do the one with 20sides

Answer 2

162

Answer 3

correct