<P> In geometry, a spherical shell is a generalization of an annulus to three dimensions . It is the region between two concentric spheres of differing radii . </P> <P> The volume of a spherical shell is the difference between the enclosed volume of the outer sphere and the enclosed volume of the inner sphere: </P> <Dl> <Dd> V = 4 3 π R 3 − 4 3 π r 3 (\ displaystyle V = (\ frac (4) (3)) \ pi R ^ (3) - (\ frac (4) (3)) \ pi r ^ (3)) </Dd> <Dd> V = 4 3 π (R 3 − r 3) (\ displaystyle V = (\ frac (4) (3)) \ pi (R ^ (3) - r ^ (3))) </Dd> </Dl>

What is the volume of a spherical shell