To find the measure of each side of a square when given the area, you need to take the square root of the area. In this case, the area of the square public plaza is 100 sq m.
Therefore, to find the measure of each side:
1. Take the square root of 100:
√100 = 10
So, the measure of each side of the square public plaza is 10 meters.
Therefore, the correct answer is:
D. 10 m
