THE EARTH
    The Earth is the third planet from the Sun,and only the planet which life exist. 3/4 of the earth's surface is covered with water,mostly by its oceans. The remaining s the land consisting of continents and islands that together have many lakes,rivers and other sources of water that contribute to the hydrosphere. The majority of the Earth's polar regions are covered in ice,including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core,a liquid outer core that generates the Earth's magnetic field.