Answer:
r = 6cm
Step-by-step explanation:
The formula for volume of a cylinder is
V = pi r^2h
where r is the radius and h is the height
We know the volume and the height
252 pi = pi * r^2 *7
Divide each side by pi
252 pi/pi = pi/pi * r^2 *7
252 = r^2 *7
Divide each side by 7
252/7 = r^2 *7/7
36 = r^2
Take the square root of each side
sqrt(36) = sqrt(r^2)
6 = r