Final answer:
Without knowing the specific rate of leakage, the tank's size, and other pertinent details, we cannot accurately conclude whether a leaking tank must have contained more than 30 gallons. Information provided deals with the properties of materials under compression and the need for air gaps to accommodate expansion and contraction.
Step-by-step explanation:
The question pertains to whether a tank that is leaking suggests it must have contained more than 30 gallons initially. The information provided discusses the physical properties of liquids and gases, and how they behave when confined in tanks, specifically addressing issues of expansion, compression, and the necessity of air gaps in rigid containers to prevent rupture. In terms of physics, the statement that a leak implies that the tank contained more than 30 gallons initially cannot be affirmed without additional context such as the size of the tank, the rate of leakage, and the remaining volume of liquid.
We learn that both liquids and solids resist being compressed with large forces and that this resistance can cause tanks to leak or even burst if not properly designed with the ability to expand and contract. Furthermore, the information includes a discussion of volume changes in the context of a gasoline tank, emphasizing the different coefficients of expansion for steel and gasoline, which can also influence the reading on a gasoline gauge.
However, determining the original volume within the tank requires further details that are not provided in the initial question. Without knowledge of the tank's dimensions or the conditions prior to the leak, the volume that the tank held before it started leaking cannot be accurately deduced.