Answer:
The slope represents the density of the substance been represented using the graph
Step-by-step explanation:
The slope of a graph is calculated as the change in the y axis divided by the change in the X axis which is known dy/dx in the above question the Y axis is represented by the Mass of the substance and the X axis is represented by the volume of the substance hence
the change in mass ( dy ) / change in volume ( dx ) = density ( average ) of the substance. therefore the special meaning of the slope is that it represents the density of the substance being represented using the graph.