Final answer:
True - The demographic center of the US has been shifting westward since independence from England, driven by factors such as rapid western expansion, land-hunger, and political and economic motivations.
Step-by-step explanation:
True - The demographic center of the US has been shifting westward since independence from England.
The rapid western expansion of the 1840s played a significant role in this shift, as the population of the United States grew rapidly during that time period.
Americans were increasingly land-hungry as populations grew and the cheap land in the west became more attractive.
Politically and economically motivated, many Americans favored westward expansion to counterbalance the industrialized and urbanized northeast and to gain control of west coast ports for trade with Asia.