A hemispherical bowl is made of 0.5 cm thick steel. Inner radius of the bowl is 4 cm. The volume of steel used in making the bowl is
Choose the most appropriate option.
A) 55.83 cm 3
B) 56.83 cm 3
C) 113.67 cm 3
D) 58.83 cm 3
E) none of these

Rationale: inner r = 4 outer r = 4.5 formula = 2 / 3 * 22 / 7 ( r ^ 2 - r ^ 2 ) ( 2 / 3 ) * ( 22 / 7 ) * ( 4.5 * 4.5 * 4.5 - 4 * 4 * 4 ) = 56.83 answer : b
Answer: B