Answer:
The formula for the area of a circle is:
A = πr^2
where A is the area and r is the radius.
In this case, we are given that the area is 4π cm². Solving for the radius, we get:
4π = πr^2
r^2 = 4
r = 2
So the radius of the circle is 2 cm.
The formula for the circumference of a circle is:
C = 2πr
Plugging in the value for the radius, we get:
C = 2π(2) = 4π
Therefore, the circumference of the circle is 4π cm.