Question

The earth crust is unstable.explain it's two effect on the earth's surface.

Answer 1

The earth crust is very unstable as endogenetic (internal forces) and exogenetic (external forces) act upon it . The endogenetic forces cause the the movement of tectonic plates ( continental plates and Oceanic plates)
The exogenetic forces on the other hand levels down the uneven areas of the earth crust and provides a graded profile of the earth crust.

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