If a circle has a radius of 5, what is its circumference?

To find the circumference of a circle, you can use the formula:

Circumference = 2πr

where ( r ) is the radius of the circle. In this case, the radius is given as 5. Substituting this value into the formula provides:

Circumference = 2π(5) = 10π

Thus, the correct answer is 10π, which represents the total distance around the circle. The circumference is a direct measurement related to the radius, and using the formula ensures that you accurately account for the geometry of the circle.