Answer:
1) ∠C corresponds to ∠R
2) ASA
3) Two obtuse angles cannot be supplementary
Explanation:
1. When you draw out the triangle, you could see which angle correspondents with each angle.
2. Unsure since it has been a while but I believe it is Angle-Side-Angle since you are provided with each angle and it says that they are congruent to each other so it would most likely be angle side angle. (This one is possibly wrong but its just a suggestion)
3. Two obtuse angles cannot be supplementary since they are both wide angles needing to be adding up together to be 180°. But in this case the two obtuse angles could both be 120° and 120°, which that would not be equal to 180°.