V = ( 4/3 ) × π × r^3
V = ( 4/3 ) × π × ( 6/2 )^3
V = ( 4/3 ) × π × ( 3 )^3
V = ( 4/3 ) × 3 × 9 × π
V = 4 × 9 × π
V = 36 π m^3
Thus the correct answer is option D .
