Recognize and interpret linear, semilog, and log-log scales and calculate slopes from data found in figures, graphs, and tables
Scales and plots assist in the graphical representation of data. A linear scale marks units by an equal difference in value between each mark (e.g. the marks -5, 0, 5, 10, 15, 20... all differ from the next by a value of 5) and is helpful in the display of data that is in a closer range of values. A logarithmic scale assigns its marks based on a multiple or ratio relative to its neighboring mark, such that the same distance between marks portrays an unequal difference in values (e.g. the marks 10-1, 100, 101, 102... all differ from the next by a multiple of 10), making log scales better suited for display of data that covers a wide range of values.
The scales used on the x- and y-axes of a plot will characterize it as linear, semi-log, or log-log. Namely, a plot with one axis using a linear scale and the other axis using a log scale is a semi-log plot (either axis may be the log axis), while a log-log plot will utilize a log scale on both axes.