Question 66407
lwt us convert the whole question into feet. I mile=5280 feet

so the x distance on a graph will be 17160 feet

the slope of the graph can be found by the equation rise/run or Y2-Y1/X2-X1
fisrt you must find the 2 points on the graph to find the slope.
these were given in your data,

the first position is x, this is at zero. and Y is at 1800 feet so you have the point (0,1800)
the second point is also given, where x is 17160 feet away, and where he stopped y=0

so your two points are (0,1800) and (17160,0)
so in the equation you will get

0-1800/17160-0=slope
the slop of your graph is (+/-)0.104895 where depending on your view is positive or negative.