I believe the answer is earthquakes.
A. Northern - it is nearer the equator than the other parts of Australia, so the temperatures would be hotter, and almost the same with tropical countries. Darwin, for example, experiences monsoon rains and storms, and high humidity, which is much different from other Australian places.
Although coal is Kentucky's primary energy source, the state also produces oil and natural gas
The correct answer is - biomass from the decomposing grasses.
The Midwest is a region known for its highly fertile soil. The reason for this is that the weathered bedrock combines with huge amounts of biomass. The biomass is almost entirely form the grasses. The grasses grow naturally in this region and they dominate the landscape. They grow and die out relatively quickly, as most of those grasses are one season grasses. They manage to create very large amounts of biomass every year, and also they decompose very quickly. The grasses also are high in nutrients, so once decomposed, they give the soil a lot of nutrients as well, which makes it very fertile and suitable for agriculture.
