Alternate exterior angles are formed by a transversal intersecting two parallel lines, therefore, your alternate exterior angles are <1 and <5.
Your alternate interior angles are <2 and <6/ <3 and <7.
Corresponding angles are formed when two parallel lines are intersected by a transversal. (<1 and <3)
Vertical angles are formed when two lines intersect each other. Therefore, <1 and <7 fall into this category.
