Answer:
Influx of gold and silver
From an economic viewpoint the discovery of new silver and gold deposits as well as the productivity increase in the silver mining industry perpetuated the price revolution. ... Also during this time the Spanish and Portuguese brought a large amount of gold from the New World to Europe.
I am assuming you are talking about the US. So in the North they have Rocky Poor Soil.
The Ice Age ended and the climate changed
The answer is B. Rice because of their clay like soil. :)
The Corps of Discovery refers to the military unit that took a two year expedition with Lewis and Clark in order to explore the land recently bought by the US government from France. This territory became known as the Louisiana Purchase.
When exploring with Lewis and Clark, the Corps of Discovery went through several different states that exist today. This includes Kansas, Nebraska, Montana, Idaho, and Washington. Essentially, this route went from Missouri to the Pacific Ocean in Washington, covering the middle of the continental US all the way to the Northwest corner of the US.