In classical fluid mechanics we treat all fluids using the concept of the continuum. This means that a) the effect of individual molecules and atoms in the fluid can be determined. b) all fluid properties have a definite value at every point in space. c) values of fluid velocity depend on the molecular concentration in that part of the fluid. d) the fluid properties are constant over the entire domain of the fluid. e) only the density of the fluid needs to have a definite value at every point in space.

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