Answer:
The radius is 4cm.
Explanation:
Formula: V = πr²h
Given:
V = 64π cm²
h = 4 cm
Asked: radius 'r'
Solve for the value of radius:
V = πr²h
64π = πr²(4)
64π = 4πr²
Divide both sides by 4π
64π/4π =4πr²/4π
16 = r²
Extract the square root
r = +-4
Take only the positive value as we're dealing with dimensions
r = 4cm