To determine how point Z relates to line segment \( \overline{XY} \), we need to understand the concept of a bisector. A bisector of a line segment divides it into two equal parts.
Given that \( XY = 22 \) units, if Z is the midpoint of \( \overline{XY} \), then it divides \( \overline{XY} \) into two equal segments. This means:
\[ ZY = \frac{XY}{2} = \frac{22}{2} = 11 \text{ units} \]
Therefore, the correct response is:
Point Z is the midpoint of \( \overline{XY} \). \( ZY = 11 \) units.