The domain is the x-values used by the graph.
The range is the y-values used by the graph.
With respect to the x-axis, the graph starts at 0 on the left and goes as far as x=15.
With respect to the y-axis, the graph starts as low as 0 (vertically) and goes as high as 75.
The range is 0≤x≤15.
The domain is 0≤y≤75.