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.
Answer:
Explanation:
Measuring the amount of deu terium in the universe allows us to set a limit on the density of ordinary matter of universe. Density of the universe is about 9×10-27 kg m-3, because of the way in which deu terium was created in the Big B ang, an exact measurement of the amount of deuterium would allow scientists to set limits on the models of the great explosion.
West Africa is mostly a region of plains. Climates range from arid to tropical and they have important agricultural and mineral resources.
It tells you that there used to be an ocean in the area the rock was found.