Answer: 224 cubic feet
Step-by-step explanation: If the base of the tank is 56 sq feet in area then the dimensions could be, (2,28) (4,14) (7,8) for example. However, it doesn't really matter. It's only important that the information we know is that it is area and there are two dimensions. Since volume is determined by base x width x height, we do 56 x 4. Or using one of the factored pairs that works, for example, 8 x 7 x 4 = 224.