Answer: The Jolene's unit rate in dollars per pound of grain is 0.25.
Explanation:
It is given that the Jolene is making a line graph that represents the price of grain and the number of pound purchase.
The number of pounds are shown on x-axis and the price in dollar are shown on y-axis.
The cost of 1 pound is 0.25, therefore the point (1,0.25) lies on the line.
The cost of 4 pound is 1, therefore the point (4,1) lies on the line.
The unit rate in dollars per pound of grain is the the slope of the line.
The slope of a line is,
Therefore, Jolene's unit rate in dollars per pound of grain is 0.25.