Question

what is the smallest angle of rotational symmetry for a square? 45° 90° 180° 360°

Explanation:

Step1: Recall the formula for rotational symmetry angle

The formula for the smallest angle of rotational symmetry of a regular polygon is $\frac{360^{\circ}}{n}$, where $n$ is the number of sides.

Step2: Identify the number of sides of a square

A square has $n = 4$ sides.

Step3: Calculate the angle

Substitute $n = 4$ into the formula: $\frac{360^{\circ}}{4}=90^{\circ}$.

Answer:

$90^{\circ}$ (the second option)