I think your answer would be b.
The quartz is more resistant to abrasion and chemically more resistant than the feldspar. The result is that the quartz remains in the stream but the feldspar breaks down to clay or is dissolved.
(this is from coursehero.com)
Answer:
This is the best explanation for why there is such a small amount of phosphorus that moves into aquatic systems:
1. Phosphorus is highly stable in the atmosphere and remains there for long periods of time.
Explanation:
The phosphorus first cycle is the process by which the phosphate ion passes in very small amounts through the lithosphere from volcanic aeorosols, then to the hydrosphere, where it stays from 20,000 to 100,000 years in the ocean, and finally to biospherere, where rain and erosion helps washing the phosphorus from the rocks into the soil. So, raining is the beginning of the phosphorus´s second cycle, so it is also, the slowest one of the matter cycles that is why the natural total background phosphate levels in several bodies of freshwater range from 0.005 to 0.05 mg/L. Phosphorus remains mostly on land and in rock and soil minerals.
Although abundant on our planet´s sedimentary rock crust and in human body, phosphorus to commercialize is only found in minerals therefore, phosphates mining activity and calcium heating is the only way to get it in its pure elemental form. It is an essential nutrient for plants and animals and a big percentage of the mined phosphorus is used to make fertilizers.
Population means the number of people in a geographic area. It can also be used for subgroups of people or animals.
Answer:
The speed of the current climate change is faster than most of the past events, making it more difficult for human societies and the natural world to adapt. Now, day by day new technologies are invented, causing more pollution than in the past. It is important now because we are developing in very fast steps and something should be done.