Which new legal idea was introduced by the signing of the Magna Carta?

Originally issued by King John of England (r. 1199–1216) as a practical solution to the political crisis he faced in 1215, Magna Carta established for the first time the principle that everybody, including the king, was subject to the law.

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the of atp are the key to its ability to store and supply energy;

phosphate

the phosphate groups of atp are the key to its ability to store and supply energy. atp releases energy when it breaks bonds between its phosphate groups.