5. If p || q, which pair of angles must be congruent?
1 and 8
2 and 5
4 and 6
7 and 8

Answer:
1 and 8.
Step-by-step explanation:
Two angles will be congruent if both measure the same. Then, as p is parallel to q we have that the alternate external angles (pair of angles out of the parallel lines, one on the right of the transversal line and the other on the left of the transversal line) has the same measure. In this case, 1 and 8 are alternate external angles.