<Tr> <Td> Any rotated figure (washer method; calculus required) </Td> <Td> π ∫ a b ((R O (x)) 2 − (R I (x)) 2) d x (\ displaystyle \ pi \ int _ (a) ^ (b) \ left ((\ left (R_ (O) (x) \ right)) ^ (2) - (\ left (R_ (I) (x) \ right)) ^ (2) \ right) \ mathrm (d) x) </Td> <Td> R O (\ displaystyle R_ (O)) and R I (\ displaystyle R_ (I)) are functions expressing the outer and inner radii of the function, respectively . </Td> </Tr> <P> The above formulas can be used to show that the volumes of a cone, sphere and cylinder of the same radius and height are in the ratio 1: 2: 3, as follows . </P> <P> Let the radius be r and the height be h (which is 2r for the sphere), then the volume of cone is </P> <Dl> <Dd> 1 3 π r 2 h = 1 3 π r 2 (2 r) = (2 3 π r 3) × 1, (\ displaystyle (\ frac (1) (3)) \ pi r ^ (2) h = (\ frac (1) (3)) \ pi r ^ (2) \ left (2r \ right) = \ left ((\ frac (2) (3)) \ pi r ^ (3) \ right) \ times 1,) </Dd> </Dl>

What is the correct si unit for volume