Given the task definition and input, reply with output. In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

Two common ways of writing it are sa / vol or SA : V. Either of these say to divide the surface area by the volume .
The surface-area-to-volume ratio , also called the surface-to-volume ratio and variously denoted sa / vol or SA : V , is the amount of surface area per unit volume of an object or collection of objects .