Deserts are A) dry with little organic matter. Although it seems that D might be correct in fact it is not because desert soil is not totally unable to support plant life because in fact some plants grow in the desert and especially following a rain storm the desert can bloom with plant life.
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.
The main mechanism through which the layering happened is gravity: it pulled the heavier, denser material to the center, leaving the less dense material on the surface.
The material that was on the outside cooled quicker, but this was the result, not the cause.
The answer is
<span>2) Gravity caused more-dense material to move toward the center of each planet.</span>
An imaginary line that crosses Ecuador
Answer:
The east are closer to the equator.