Answer:
Rate of change = 6 miles per hour
Step-by-step explanation:
Rate of change of the line is represented by the slope of the line.
Formula to get the rate of change is,
m = [tex]\frac{\triangle y}{\triangle x}[/tex]
From the graph attached,
Given straight line is passing through two points (2, 12) and (4, 24).
Rate of change = [tex]\frac{y_2-y_2}{x_2-x_1}[/tex]
= [tex]\frac{24-12}{4-2}[/tex]
= 6
Rate of change of the line = 6 miles per hour
Therefore, rate of change of the graph will define the speed of Arlene.