Question

which shape has at least one pair of perpendicular sides?

Explanation:

Step1: Recall Perpendicular Sides

Perpendicular sides meet at a right angle ($90^\circ$).

Step2: Analyze Each Shape

• First shape (trapezoid): Non - right trapezoid, no perpendicular sides.
• Second shape (parallelogram): Sides are parallel, no right angles.
• Third shape (square): All angles are $90^\circ$, so adjacent sides are perpendicular.
• Fourth shape (triangle): A typical triangle (not right - angled) has no perpendicular sides.

Answer:

The third shape (the square)