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The Fertile Crescent is basically where human civilization started. It stretches from Mesopotamia and across the Mediterranean coast to Egypt. Early civilizations depended on agriculture. To make agriculture, you need a river because it is a good water source to help grow your crops.
If you look at the map I have provided below, you will see that there are tons of rivers. This would make it very easy for settlers to grow crops. This means that sea tides and eroding mountains aren't the answer. I don't think the rivers were flooding and natural canals is an oxymoron because canals are artificial waterways, but this all should give you and idea.
Have a wonderful day! :D
Lava that cools so quickly that the ions do not have time to arrange themselves into crystals with definite shape will form igneous rocks with FINE GRAINED TEXTURE. Igneous rocks are those rocks formed as a result of cooling of magma or lava.
i. Using fossil evidences
ii. Similar rock lithologies at the edges of continent
iii. Climate clues
iv. Fitting of the continents into a puzzle
v. Sea floor spreading
Explanation:
Pangea was a super-continent on the earth which formed about 330 million years ago during the Paleozoic and began breaking up during the early Mesozoic, about 175 million years ago.
Most of the present day continents formed as a result of the separation of the Pangea in the early Mesozoic.
The first scientist to propose the existence of this super-continent was Alfred Wegener in 1912. He suggested the continental drift hypothesis to explain the separation of the land masses.
Today, the theory has been revised to the theory of plate tectonics which provides a better mechanism to understand the drifting of the continents.
Here are some of the evidences to support the existence of Pangea;
- Using fossil evidences: Mesosaurus, a reptile animal that lived during the Permian, was found in both South America and Southern Africa. Since this animal could not swim nor fly, only a jointed landmass could have made them present in both continents.
- Similar rock lithologies at the edges of continents: rock formations at the Western edge of Africa and South - Eastern part of Brazil matches with one another and have been believed to be once joined together.
- Climatic clues such as glacial tills that are confined to temperate and polar regions have been found in tropical regions.
- Wegener fitted the present day continent into a giant supercontinent and this provided a visual support for his claim.
- Evidences from sea floor spreading revealing magnetic reversals at divergent margins suggests the prevalence of plate tectonics i.e moving plates on earth.
This among many other evidences underscores the existence of a supercontinent called Pangea.
Since M is the midpoint of the segment AB
then measure of AM and MB are equal. So to solve the value of x, equate the following
measurement
AM = MB
50 – 3x = -20 + 4x
70 = 7x
<span>X = 10</span>
