Find the volume of a sphere with a radius of 3 cm.

Step 1 ：The formula to find the volume of a sphere is \( V = \frac{4}{3} \pi r^3 \)

Step 2 ：Substitute the given radius of 3 cm into the formula: \( V = \frac{4}{3} \pi (3)^3 \)

Step 3 ：Calculate the volume: \( V = \frac{4}{3} \pi (27) \)