A slope is also known as the gradient of a line is a number. The correct option is B.
What is Slope?
A slope is also known as the gradient of a line is a number that helps to know both the direction and the steepness of the line.
slope = (y₂-y₁)/(x₂-x₁)
The rate of change shown in the graph is the slope of the given line.
Now, to know the slope of the line consider any two points on the line, such as (0,0) and (5,400).
Therefore, the slope of the line can be written as,
Slope, m = ($400 - $0)/(5-0) hour
= $400/5 hour
= $80/hour
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