solve this---**Question Number:** 30
**Diagram Description:**
- Type: Geometric figure (quadrilateral ABCD).
- Points: Labeled vertices A, B, C, D.
- Lines: Line segments connecting A to B, B to C, C to D, and D to A, forming a closed figure.
- Angles: A right angle is indicated at vertex C by a square symbol.
- Relative Position: The figure is oriented such that AD is the bottom horizontal line, CD is a vertical line segment on the right, BC is a horizontal line segment above CD, and AB is a slanted line segment connecting A on the left to B on the top right. A is to the left of D, B is above the line AD and to the left of C.
**Textual Information:**
**Question Stem:**
In quadrilateral ABCD above, AD || BC and CD = 1/2 AB. What is the measure of angle B?
**Given Conditions/Equations:**
AD || BC
CD = 1/2 AB
**Question:**
What is the measure of angle B?
**Options:**
A) 150°
B) 135°
C) 120°
D) 90°
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In this problem, we have a quadrilateral ABCD where AD is parallel to BC, and CD equals one-half of AB. We need to find the measure of angle B. Let's analyze the properties of this quadrilateral to solve the problem.