The construction of the hoover dam on the colorado river in 1936 led to

The fact that the dam project created so many jobs was extremely beneficial to society because many men had lost their jobs to the great depression. Also, the promise of jobs attracted people out to the western area where the Hoover Dam is located, promoting the economic and social growth of that region.Apr 28, 2014

The highest point of a hill (or mountain) is a single point.
a single point can only be precisely marked with a dot. 
putting on a contour line is impossible  on a single point because the contour line is created after multiple points that have the same hight are marked, and after that, all of those points are connected with a line that creates a closed area. so the highest point, as said above, is a single point, there are no other points with the same height, so the only possible way for it to be marked is with a dot, and there is no possibility for a contour line.

Women have jobs, can become a high ranking of citizen such as president or governor and women doesn't have to have a husband or children.