Daniel Boone is linked to the exploration of

This term refers to the number of people per unit area (usually a kilometer or a mile). this could refer to the number of people per square mile in a city, a county, a province, a state, or a nation.

How does specialization enable countries to trade with one another? a country can make and sell goods affordably and buy goods that it is inefficient at making. a country can make what it chooses and sell its goods to other countries. a country can decide to buy everything it needs from other countries. a country can efficiently make goods that were once difficult to make.

The biggest component / ingredient of summer time smog is