Answer: (C) A hot spot
Explanation:
A hot spot is created in the volcanic peaks and it is basically developed over the plume. The mantle plumes are the areas of the up-welling and the hot mantle areas. Magma created by the problem area ascends through the unbending plates in the lithosphere layer.
It produces the dynamic volcano at the surface of the earth. In the mantle area, the hot spot are generated in which the rocks are get melted for generating the magma. The hot spot generated the heat are basically comes from the middle of the earth.
Answer:
The sun
Explanation:
“Approximately 4.6 billion years ago, the solar system was a cloud of dust and gas known as a solar nebula. Gravity collapsed the material in on itself as it began to spin, forming the sun in the center of the nebula. With the rise of the sun, the remaining material began to clump together.“
<span>The
higher the altitude, the lower the atmospheric pressure. Lower pressure
in turn causes water to evaporate more quickly, and water actually
boils at a lower temperature. The percentage of oxygen in the air at two
miles (3.2 km.) is the same as at sea level (21%). However, the air
pressure is 30% lower at the higher altitude due to the fact that the
atmosphere is less dense--that is, the air molecules are farther apart.
The important effect of this decrease in pressure is this: in a given
volume of air, there are fewer molecules present. This is really just
another way of saying that the pressure is lower. This is called Boyle's
law.</span>
Unitary: no local decisions.
Federal: some local decision.
Confederation: a lot of local decisions.
