In stage 1 the two rates are balanced. In stage 2 they diverge , as the death rate falls relative to the birth rate. In stage 3 they converge again, as the birth rate falls relative to the death rate. Finally in stage 4 the death and birth rates are balanced again but at a much lower level.
<u>Answer:</u>
<u>The Continental drift</u> is the displacement of continental masses relative to each other. This hypothesis was developed in 1912 by Alfred Wegener, who affirmed <u>that thousands of years ago there was a single and unique supercontinent, called </u><u>Pangea</u><u>, which later became separated.
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His formulations were based mainly on the way in which the forms of the continents seem to fit on each side of the Atlantic Ocean, such as Africa and South America. He also took into account the distribution of certain fossils that coincided in continents far from each other.
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At first this approach was discarded by most of his colleagues, because <u>
his theory lacked a logical and geological explanation for its epoch. </u></h2><h2>
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He proposed that the continents move on another denser layer of the Earth that made up the ocean floor. But it was not until the 1960s, with the development of the theory of tectonic plates, that the movement of the continents could be adequately explained.
Yes because rivers are important for trade and even things like fresh water and transport.