Over the past 50 years in the United States, the populations of (Points : 5)
suburbs have increased while city centers have declined.
suburbs and rural regions have increased while ...
... city centers have also increased.
city centers have increased while suburbs and rural regions have declined.
city centers and rural regions have increased while suburbs have declined.
... deposits have been found in India, Germany and, in the United States ... and humans, over 50 percent of wetlands in the lower 48 states have ... [ surrounding suburbs into rural ... ...