Which of the following describes how to determine the slope of a truss?

Determining the slope of a truss involves calculating the vertical rise over a specified horizontal distance, typically measured over 12 inches, which gives a clear and standardized way to express the angle of the roof. This calculation provides a ratio that is essential in understanding how steep the truss is. By using the rise in vertical height (the change in elevation from one point to another along the truss) and dividing this by the horizontal distance (the span over which this rise occurs), you can effectively determine the slope in a manner that can be consistently understood and communicated.

The other options, while related to trusses, do not accurately describe the proper method to calculate slope. Simply measuring the edge of the roof does not account for the vertical aspect needed to determine the slope. Calculating the total length of the trusses does not provide information about how steep they are. Lastly, assessing the internal angle might give some indication of the truss' configuration, but it does not provide the necessary rise-over-run calculation that clearly defines the slope.