The correct answer is - A. replacing natural vegetation with cultivated crops.
The natural vegetation is perfectly adapted to a certain environment, and it is also able to keep the soil tight with its roots, so the erosion is minimal.
When the natural vegetation is replaced by cultivated crops, than a problem occurs in the erosion of the soil. That is because the cultivated crops, in general, do not have root systems that are as strong and widespread as the natural vegetation, thus the soil becomes loosened up, so it is much easier to be eroded.
Answer: He found a rock, and the crystals inside are minerals.
Options:
- He found a rock, and the crystals inside are minerals.
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He found a mineral, and the crystals inside are rocks.
- He found a rock, and the crystals inside are rocks, too.
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He found a mineral, and the crystals inside are made of dirt.
Explanation:
A rock differs from a mineral. While they are both solid, a mineral has a crystalline structure while a rock does not have a specific structure. Rocks are made up of different mineral structures and that is what Joseph discovered on dropping the rock, one of the component minerals in the rock. For example, a type of rock, slate may consist of feldspar, quartz among many other minerals.
Answer:
Volcanic islands are formed as a crustal tectonic plate containing an ocean moves over a magma hot spot.
... This magma carries an enormous amount of heat, and it can then be released into the crust and createmagma chambers there.
