The waterways and mountains
of the United States, much like the rest of the world, have had a significant
impact on where people settled and how towns and cities interacted with one
another. Large mountain ranges served as natural barriers between groups,
causing distinct regional shared cultures to develop due to the relative
isolation and shared geography that mountain ranges create. The opposite is
true for rivers, which connected communities through ease of travel, trade, and
shared access to water and other natural resources.
The given mortality rate is understood to be <em>deaths per thousand per year</em>. So, among 10 thousand people, one might expect 10×7.4 = 74 deaths per year.
