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naturalGas

Fossil fuel energy source consisting largely of methane and other hydrocarbons

meta

supertypes

marker

Marker labels a dict with typing information

    phenomenon

Aspect of scientific interest with measurable quantities

        substance

Matter in one the three states solid, liquid, or gas

            fluid

Liquid or gas

                gas

Substance with neither definite volume nor shape

quantities

flow

Measure of volumetric flow of fluid

level

Fill level of a vessel containing a fluid where 0% is empty and 100% is filled

pressure

Measure of force applied

temp

Temperature - measure of hot and cold