Which units can be used for measuring carbon dioxide in liquid form?

Pounds or kilograms are indeed the correct units for measuring the mass of carbon dioxide in liquid form. When dealing with substances like carbon dioxide, especially in a liquid state, mass is a critical measurement because it relates directly to how much of the substance is present.

Using pounds or kilograms provides a clear understanding of the quantity in terms of weight, which is important for processes that require precise handling of gases in liquefied forms. This measurement is particularly relevant in industrial applications, where calculations involving the mass of materials are necessary for safety, efficiency, and compliance with regulations.

Other options involve units that are appropriate for different contexts. For instance, gallons or liters pertain to volume measurements, which are not directly related to the mass of a liquid. Similarly, ounces or grams also deal with mass, but they are more suited for smaller quantities, which may not be practical for larger amounts of carbon dioxide. Lastly, feet or meters are measures of length, entirely unrelated to the measurement of carbon dioxide in any state. Thus, pounds or kilograms are the most relevant and appropriate units in this scenario.