Final answer:
The rise and run determine the slope of a line on a graph. In the context of changes in air density with increasing altitude, the rise and run corresponding to a negative slope would be a rise of -4 and a run of 1, as indicated in option (a).
Step-by-step explanation:
To identify the rise and run of a graph, we need to analyze the change in the y-axis (rise) over the change in the x-axis (run). This concept is critical when discussing the slope of a line on a graph. Given the options provided, we look for a rise of -4 and a run of 1, which indicates that for every unit of increase in the independent variable (x-axis), the dependent variable (y-axis) decreases by 4. This corresponds to a steep downward slope. However, the examples related to altitude and air density presented here describe a situation where the rise is a decrease in density (from 0.100 to -0.207, which is a change of -0.307) over an increase in altitude (from 4,000 meters to 6,000 meters, which is a change of 2,000 meters). This results in a negative slope indicating that air density decreases as altitude increases.
Therefore, based on the descriptions provided, which discuss changes in air density over altitude, we can conclude that the correct rise and run related to a negative slope and depicted in the examples would be option (a): The rise is -4 and the run is 1.