The statement that is true about the graph as it relates the unit rate is:
d. The unit rate is $22.50 per hour
Unit rate of a relationship between two variables, x and y, that are proportionally related can be found using k = y/x, where k is the unit rate.
Given that:
x = hours he worked
y = his total earnings
We are told that (4, 90) is a point on the graph.
Using the point, (4, 90), we can find the unit rate as shown below:
k = y/x = 90/4
k = 22.5
Therefore, the statement that is true about the graph as it relates the unit rate is:
d. The unit rate is $22.50 per hour
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