Given the line on the graph, we have that it passes through the points (1,25) and (2,50), then we can find the relation function with the slope-point equation of the line:
we have that the cost of the dirt is given by the equation y=25. To find how much would it be for 40 cubic yards of dirt, we make x=40 and we get the following:
therefore, the cost to haul 40 cubic yards of dirt is $1000