What does the first law of thermodynamics state?

a) if two systems are in equilibrium with a third, then they are in equilibrium with each other.
b) there is and always will be the exact same amount of energy in the universe.
c) as temperature approaches absolute zero, the entropy approaches a constant minimum.
d) entropy of an isolated system tends to increase.

b) There is and always will be the exact same amount of energy in the universe.

Explanation:

The first law of thermodynamics establishes the principle of energy conservation, that is to say that in any process the energy is not destroyed, it only transforms into another type of energy, so when analyzing thermodynamic systems it is established that the energy that enters A system is the same that comes out. For the above reason, it can be inferred that if the energy is not destroyed or created there will always be the same amount of energy in the universe.

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