Answer:
<u><em>River valley civilizations</em></u>
Explanation:
They were centred around various river valleys as their main source of livelihood and the flourished only due tiote river valley on which they were based. Like the harappan in Indus Valley, The yellow river (Huang He), the Mesopotamia around Tigris and Euphrates and the egyptian Nile.
1.weathered materials from rocks and transported to the beach through wind and rivers
2.from rocks weathering and eroding over thousands and millions of years.
<span>biogeochemical cycles</span>
Answer: The Earth's crust that formed these mountains was once covered with an ocean
Basically the Earth is layered because of gravity. The earth formed in the molten state. The liquid iron which is very dense fell to the center. The rest of the earth is made up of silicate materials with SiO2 being the main component.
hope this helps!
