Renewable energy is energy that doesn't run out.Examples of these are wind and water. Nonrenewable energy sources are things like oil and coal—fossil fuels, because once they're gone, we're not getting them back. but we'll always have wind and water.
Explanation: The standard unit of velocity is metre per second. Velocity can be defined as the displacement of a body per unit time.
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.
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