To what percentage of its water capacity can a container be filled with propane?

The correct answer reflects the industry standard for filling propane containers. Propane is typically filled to a maximum of 80% of the container's water capacity to allow for the expansion of propane as it is subjected to temperature changes. This is crucial because propane expands and contracts with temperature fluctuations. Filling the container to 80% ensures there is adequate space for the liquid propane to expand when it warms up, preventing excessive pressure build-up that could lead to leaks or explosions.

The 80% fill rule is a safety regulation that is widely adhered to in the propane industry. This standard helps maintain safe operating conditions and mitigates potential hazards associated with liquid propane storage. It is important for anyone working with propane to understand this filling guideline to ensure safe handling practices.