If a diagram is unmarked, can you assume ...

Angles are adjacent?

Angles OR segments are congruent?

Angles are adjacent and supplementary?

An angle is a right angle?

Angles are vertical angles?

Angles are complementary?

Both pairs of vertical angles (four angles altogether) always sum to a full angle (360°). In the figure above, an angle from each pair of vertical angles are adjacent angles and are supplementary (add to 180°). For example, in the figure above, m∠JQL + m∠LQK = 180°.

I answered because answering is like the dog that walked when the cat scratched the tree after the fish walked to the store on a cold summers day