Explanation:
Except in the crust, the interior of the Earth cannot be studied by drilling holes to take samples. Instead, scientists map the interior by watching how seismic waves from earthquakes are bent, reflected, sped up, or delayed by the various layers.
By observing how seismic waves are absorbed and refracted, scientist have been able to work out where the properties of the earth change dramatically. our understanding of the internal structures of the earth and the size of its core is based on these observations.
basically:
size of core
structure of the earth I.e. the layers of the earth
and I think the last one is how the internal structure is changing? not sure on the last one but its still a solid guess.
Answer:
The rivers coming from the northern mountains carry alluvium with them and do the depositional work. In the lower course, due to gentle slope, the velocity of the river decreases which results in the formation of riverine islands.
Explanation:
I belive it it O because <span>An O horizon has at least 20% </span>organic matter<span> by mass. Two main scenarios result in the formation of an O horizon: saturated, </span>anaerobic<span> conditions (wetlands) or high production of leaf litter in forested areas. Anaerobic conditions slow the </span>decomposition<span> process and allow organic material to accumulate. An O horizon can have various stages of decomposed organic matter: highly decomposed, sapric; moderately decomposed, hemic; and minimally decomposed, fibric. In a fibric O layer, plant matter is recognizable (e.g., it is possible to identify a leaf). Sapric material is broken down into much finer matter and is unrecognizable as a plant part. Hemic is in between sapric and fibric, with some barely recognizable plant material present. It is possible to have multiple O horizons stacked upon one another exhibiting different decomposition stages. Because of their organic content, these horizons are typically black or dark brown in color. The dominant processes of the O horizon are </span>additions<span> of organic matter, and </span><span>transformations </span><span>from fibric to sapric
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The correct answer is (c.) troposphere
The troposphere is the lowest portion of the atmosphere but also it is where most gas particles are located. It holds 75 percent of the atmosphere's mass. It is typically a hundred meters deep to 2 km. Above the troposphere is the tropopause, bordering between troposphere and the stratosphere.