Answer:
The radius is 9 mm
Explanation:
The volume of a sphere is given by
V = 4/3 pi r^3 where r is the radius
972 pi = 4/3 pi r^3
Divide each side by pi
972 = 4/3 r^3
Multiply each side by 3/4 to isolate r^3
3/4 * 972 = 4/3 * 3/4 r^3
729 = r^3
Take the cube root of each side
(729) ^ (1/3) = (r^3) ^ (1/3)
9 = r
The radius is 9 mm