When 1 liter of water is heated from 10 to 20 ° C, 42 kJ of energy is transferred to it. How much heat will be released

When 1 liter of water is heated from 10 to 20 ° C, 42 kJ of energy is transferred to it. How much heat will be released when it cools to its original temperature?

42 kJ will be allocated, because in an ideal system, the energy spent on heating a body is equal to the energy released when the same body is cooled to its initial temperature.

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