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The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table; in other words, below the level of the water table the soil pores and rock fractures are saturated with water. An aquifer is a layer within the zone of saturation that can readily yield and store water, such as in interconnected spaces (fractures, cracks, poor spaces, etc.) that can provide a source of water for a well.
By 1921, the British Empire ruled a population of between 470 and 570 million people, approximately one-quarter of the world's population. It covered about 14.3 million square miles (more than 37 million square kilometers), about a quarter of Earth's total land area. Though it has now mostly evolved into the Commonwealth of Nations, British influence remains strong throughout the world: in economic practice, legal and governmental systems, sports (such as cricket and football), and the English language itself.