The Aluminum Company of America (Alcoa) formerly controlled all U. S. sources of bauxite, a key component in the production of aluminum. Given that Alcoa did not sell bauxite to any other companies, Alcoa was a monopolist in the U. S. aluminum industry from the late 19th century until the 1940s.

Which of the statements best describes why the aggregate demand curve is downward sloping? an increase in the aggregate price level causes consumer and investment spending to fall, because consumer purchasing power decreases and money demand increases. as the aggregate price level increases, consumer expectations about the future change. as the aggregate price level decreases, the stock of existing physical capital increases. as a good's price increases, holding all else constant, the good's quantity demanded decreases.