In a positively skewed (right-skewed) frequency distribution, the tail on the right side is longer or fatter. Extreme high values pull the Mean to the right more than the Median, while the Mode remains at the highest peak of the curve. Thus, the relationship is:

For symmetrical distributions: $\text{Mean} = \text{Median} = \text{Mode}$
For negatively skewed distributions: $\text{Mean} \lt \text{Median} \lt \text{Mode}$

Classification of fluid flow in hydraulics:
Steady flow: Flow parameters (velocity, depth) do not change with time at any given cross-section ($\partial V/\partial t = 0, \partial y/\partial t = 0$) -> (III).
Uniform flow: Flow parameters (velocity, depth) do not change along the length/space at any given instant ($\partial V/\partial s = 0$) -> (IV).
Non-uniform flow: Velocity changes from point to point along the length of flow ($\partial V/\partial s \ne 0$) -> (I).
Unsteady flow: Velocity and depth change with time at a given cross-section ($\partial V/\partial t \ne 0$) -> (II).

Range is the simplest measure of statistical dispersion, calculated as the difference between the largest (maximum) and smallest (minimum) observations in a sample:

It uses only these two extreme values and does not take into account any other intermediate data points.