What are the three purposes of a water column?

The water column serves three primary purposes which are accurately captured in the correct choice. The first purpose, "measure," refers to the ability of the water column to quantify the pressure of the fluid above it, often translating that pressure into a clear gauge reading. The second purpose, "record," emphasizes the capability of the water column to capture and document this pressure measurement over time, thus providing data that can be referenced for performance analysis or compliance checks. Lastly, "regulate" speaks to the water column’s role in managing pressure levels within a piping system by allowing operators to make informed decisions based on the measurements and recordings. This regulation helps ensure safety and optimal performance in high-pressure piping systems, which is crucial in preventing leaks or failures.

The other options might contain some relevant actions, but they do not fully encompass the specific roles that a water column plays in hydraulic systems. For example, "indicate" and "assess" or "monitor" and "analyze" do not highlight the proactive management aspect of regulating pressure that is vital in piping applications. Thus, the selection of "measure, record, regulate" best represents the essential functions of a water column in this context.