Final answer:
The measure of angle mED and the measure of angle ME are equal because they are both formed by the intersection of the perpendicular bisector of CD and CD itself.
Step-by-step explanation:
In this scenario, the student constructs a perpendicular bisector of CD. The perpendicular bisector is a line that intersects CD at a right angle and divides it into two equal segments. The point of intersection, E, is equidistant from the endpoints of CD.
Therefore, the relationship between the measure of angle mED and the measure of angle ME is that they are equal. Both angles are formed by the intersection of the perpendicular bisector of CD and CD itself, meaning they have the same measure.