What system focused on exports and acquiring precious metals

Mercantilism: During the Age of Exploration (late-15th, 16th, and 17th centuries), European countries such as Spain and England exploited cash crops and — especially — precious metals (gold and silver) from the Americas, West Indies, and other places outside of Europe rich with such valuable resources. This was done in order to fuel their respective empire back in Europe. Then, European countries would heavily export these products throughout Afro-Eurasia (combination of Africa, Europe, and Asia). This whole idea of exporting more than importing is known as mercantilism.

Note: The Netherlands, France, and Portugal were also involved in the mercantilist practices that Spain and England took part in during this time period (1500-1700).

In the midwest because it has more moderate climate than the north or south west which makes farming far easier.