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The westward movement of population across the United States led to expanded agricultural production. A. The desire to improve their livelihood often inspired people to move west. B. Among the people who moved to the western United States were a number of artisans. C. The fertility of western farmland as well as favorable government policies supported agricultural gains. D. Steamboats were originally used to transport passengers rather than freight. E. Commercial farming in the West was greatly enhanced by improvements in land and water transportation. F. The transportation revolution resulted in regional economies that operated independently of a national market economy.