The answer is C. 100 because the total measure of a quadrilateral is 360. When you add up the 3 interior angle measures, it adds up to 260. Then you subtract 360-260 to get 100 as the fourth angle measure. Hope that this helped!
Answer:
20/3
Step-by-step explanation:
A triangle is
A polygon with
3 angles(x2)
3 sides
