Lead sphere of diameter $6\;cm$ are dropped into a cylindrical beaker containing some water and are fully submerged. The diameter of the beaker is 18 cm and the rise in the level of water is $40 \;cm$. The number lead sphere dropped in the water is

Question

$(A) \; 100 \\(B)\;90 \\(C)\;95 \\(D)\; 80$