## Calculus (3rd Edition)

Graph of atmospheric temperature as a function of altitude with units of $F^{\circ}/ft$ or $C^{\circ}/m$.
The rate of change of atmospheric temperature with respect to altitude is the slope of the line tangent to the graph of atmospheric temperature as a function of altitude. Possible units for this rate of change are $F^{\circ}/ft$ or $C^{\circ}/m$.