The contiguous United States are framed by three major bodies of water: the Atlantic Ocean on the east coast, the Pacific Ocean on the west and the Gulf of Mexico to the south. The Pacific also holds the Hawaiian Island chain. The Gulf stretches from Texas to Florida and also touches Alabama, Louisiana and Mississippi.
I think they all identify climate regions.<span />
Because they form from many other older rock particles.
The answer which best explains why parts of southern Africa are not experiencing the same rate of population growth as others is that many people are dying young due to HIV/AIDS in southern Africa.