StandardAtmosphereData
StandardAtmosphereData[altitude,property] returns the value of the property at the specified geometrical altitude for the chosen model of the standard Earth atmosphere.
StandardAtmosphereData[layer,property] returns a piecewise symbolic approximation with the range of an atmospheric layer for the property.
StandardAtmosphereData["SymbolicApproximation",property] returns the full piecewise symbolic approximation for the property.
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