I think philosophy, science, and communication
A major difference was that Roosevelt felt that the government spending to help people who were in economic trouble, was much more acceptable than Hoover thought it was. Hoover believed in the idea of "rugged individualism" in which people are largely responsible for their own welfare.
An important contribution of enslaved Africans employed in large-scale, specialized production of commodities in the Americas is the development of price-making markets across the Atlantic basin in regions (including Western Europe) that had long been dominated by non-market-oriented production.
The President is chief of state. This means he is the ceremonial head of the government of the United States, the symbol of all the people of the nation.
