The western side is steeper because the lines are closer together than the other sides of the hill.
Explanation:
Each contour line represents a 20ft increase in elevation. You can see the 600ft line labeled on the map, so the next one in is 620, and the one labeled "X" is 640.
Contour lines that are farther apart indicate a more gentle slope that is increasing its height over a longer distance. Just like a graph in math class, slope is "rise over run," so a flatter slope tells us that the height is increasing slowly. Close contour lines show us that the height is going up very quickly.
The answer is faults because when divergent boundaries occur, the tectonic plates move away from each other, therefor creating a fault in the earths crust.
