Why is the study of populations (demography) important? how does it impact me?

Demographic studies will determine the age structure and income structure of people living in a geographic area. Businesses will use this information to help in determining if their business will succeed for given area. Cities will use that information to determine what infrastructure is needed. You would use this to detemine if the area is one you might want to move to or move from.

Earths place in space 

Answerseafloor spreading;