Define crust,mantle and core briefly

Mantle: Mantle is the widest section of the Earth. Its thickness is approximately 2,900 km. Mantle is mainly made up of semi-molten rock known as magma. The rock is hard in the upper part of the mantle, but lower down the rock is softer and begins to melt. The mantle is located directly under the Sima. The mantle consists of very hot and dense rock. This layer of rock flows like asphalt under heavy weight. This flow is because of the greatest temperature differences from the bottom to the top of the mantle. The reason behind the plates of the Earth move is the movement of the mantle. Its temperature varies between 1600 oF at the upper part to 4000 oF near the bottom.
Crust: The crust is the outer layer where we live. The thickness is around 0-60 km. It’s a solid rock layer divided into two types: Continental crust covers the land and, Oceanic crust covers water. The crust is the most widely studied and understood. Mantle is hotter and capable of flowing. The outer and inner core are much hotter with great pressures that you can be squeezed into a ball smaller than a marble if you are able to go in the center of the Earth.