The problem asks to find the circumference of circle $C$ given that the radius of the circle is 6 cm.

The formula to find the circumference $C$ of a circle is given by: $C = 2\pi r$ where $r$ is the radius of the circle.

Given: $r = 6 \text{ cm}$

Substituting the value of $r$ into the formula: $C = 2\pi \times 6 = 12\pi \text{ cm}$

So, the exact circumference of circle $C$ is $12\pi$ cm.

Would you like further details or have any questions?

Here are some related questions:

1. What is the area of circle $C$ with radius 6 cm?
2. If the radius were doubled, what would the new circumference be?
3. How would you calculate the circumference if given the diameter instead of the radius?
4. What is the numerical value of the circumference if $\pi$ is approximated as 3.14?
5. How does changing the radius affect the circumference of the circle?

Tip: Remember that the circumference of a circle is directly proportional to its radius, meaning that doubling the radius will double the circumference.