Coal-burning factories and increased automobile usage has caused the greatest increase in "<span>A) air pollution," since in fact coal when burned is one of the worst pollutants. </span>
The answer is c because this answer is the only one that makes sense
A division of labor occurred when people started producing a surplus of food because it was no longer necessary to use all of the labor force to subsist off of agricultural goods. Once a society or community can produce enough to survive and eat the labor force will begin to work in other industries creating a division of labor this could include making textiles, building homes, or any other number of economic activities.
Slaves worked for free and had to do all hard labor that they were told to do.
I believe it is the Han Dysnasty.
