The area of a circle of radius 10 units is equal to the surface area of a sphere of radius 5 units.a. trueb. false

True

Area of a circle = πr^2
So if r = 10: area = π*10^2
= 100π

Surface area of a sphere = 4πr^2
If r = 5: surface area = 4π*5^2
= 4π*25
= 100π