<u>Answer and Explanation:</u>
The mechanism which is responsible for moving the plates that bring change in the position of the continents is the convection in the asthenosphere.
Henry Hess, a geologist and an American Navy officer in the World War II, discovered that the sea floor and the the Mid Atlantic Ridge is spreading which helped the the scientists in studying and understanding the mechanism of how the plates move.
Answer:
na se nada porque no quieroooo
You would definitely not expect political stability in a state that is being annexed or which does not have a territory - rather the opposite would be true.
Both multinational and souvereign states can have a high lever of political security. However, in a multinational state one can also expect some conflicts between the different ethnic groups - therefore the best answer is "a sovereign state"
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Answer:
<h2>BIOSPHERE</h2>
Explanation:
Human beings like animals or plants are part of the biosphere, one of the spheres in the earth.
I hope this helps
Answer:
B and C
Explanation:
B. In a given rock sample, the amount of Silicon-32 isotopes gets divided in half about every 170yrs.
This is the concept of half-life. Half life is the time take for half of a radioactive isotope to disintegrate. The shorter the half life the faster the isotope disintegrates.
From the question, we were told that it would take 170yrs for half of the isotope of Silicon to disintegrate to Phosphorus. This is the half life.
C. The half life can be used to determine the amount of Si-32 that has decayed from the time closure temperature was reached.
The closure temperature is very important in radioactivity. It is the temperature at which a system has cooled and there is no resulting disintegration of parent and daughter isotopes.
From first order kinetics, we know that the rate at which radioactive elements decay at any time is directly proportional to the number of radioactive atoms present. A knowledge of the half life helps to figure out the number of atoms that has decayed in time.
