You may be offered hip replacement surgery if: 1  you have severe pain, swelling and stiffness in your hip joint and your mobility is reduced. 2  your hip pain is so severe that it interferes with your quality of life and sleep. 3  everyday tasks, such as shopping or getting out of the bath, are difficult or impossible.
The Earth consists of four concentric [concentric: Describe shapes (usually circles) which share the same centre point.] layers: inner core, outer core, mantle [mantle: A zone of hot rock in the interior of the Earth, located between the outer crust and the molten core.] and crust [crust: The outer
Sitting on top of the outer core, we find the mantle. This layer is by far the thickest layer of Earth, about 1,800 miles thick! It also makes up about 85% of Earth's volume. Like the core, the mantle contains mostly iron, but in the form of silicate rocks.