Given a cylindrical tank, in which situation will you find surface area and in which situation volume. (a) To find how much it can hold

Given a cylindrical tank, in which situation will you find surface area and in which situation volume.
(a) To find how much it can hold.
(b) Number of cement bags required to plaster it.
( c) To find the number of smaller tanks that can be filled with water from it.

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