This diagram of airport runway intersections shows two parallel runways. A taxiway crosses both runways.
How are ∠8 and ∠4 related?

∠8 and ∠4 are related as vertical angles, meaning they are congruent (have the same measure) and are located opposite each other at the intersection of the runways and the taxiway.
In the given diagram of airport runway intersections with two parallel runways and a taxiway crossing both runways, ∠8 and ∠4 are related as vertical angles.
Vertical angles are a pair of non-adjacent angles formed when two lines intersect. They have the same measure and are located opposite each other. In this case, ∠8 and ∠4 are vertical angles because they are formed by the intersection of the two parallel runways with the taxiway.
To visualize this, imagine the two parallel runways as two horizontal lines and the taxiway as a vertical line crossing them. The intersection of the horizontal runways and the vertical taxiway forms four angles. ∠8 and ∠4 are the angles that are opposite each other and have the same measure.
So, ∠8 and ∠4 are related as vertical angles, meaning they are congruent (have the same measure) and are located opposite each other at the intersection of the runways and the taxiway.