Answer:
a. 20π cm.
b. 20(√2)π cm,
Explanation:
a. The diameter (d) of the circle = side of the square = 20 cm.
So the circumference = π d = 20π cm.
b. In this case the diameter = the length of the diagonal of the square.
The diagonal = diameter of the circle =sqrt ( 20^2 + 20^2) = √800 = 20√2.
So the circumference = πd = 20(√2)π.