We have to calculate the water remaining in A after B is complete.
This will be equal to the volume of A minus the volume of B.
The volume of each cylinder is equal to the area of the base times the height, so we can calculate this difference as:
[tex]\begin{gathered} V=V_A-V_B \\ V=\pi(r_A)^2h_A-\pi(r_B)^2h_B \\ V=\pi(4)^2(9)-\pi(3)^2(11) \\ V=\pi(16)(9)-\pi(9)(11) \\ V=144\pi-99\pi \\ V=45\pi \\ V\approx141.4 \end{gathered}[/tex]Answer: the remaining volume is approximately 141.4 cubic feet.