Question

which pair of angles is complementary?

Explanation:

Step1: Recall complementary - angle definition

Two angles are complementary if their sum is 90°.

Step2: Check each pair

For the first pair: 60° + 31°=91°≠90°.
For the second pair: Each angle is 90°, and 90°+90° = 180° (they are supplementary, not complementary).
For the third pair: 56°+34° = 90°.

Answer:

The pair of angles with measures 56° and 34° is complementary.