One end of a light string is attached to a small aluminum ball inserted into a chunk of ice of mass M0 = 0.100 kg. The other end of the string is attached to the bottom of an insulated container filled with m = 0.500 kg of water. Initially, the tension in the string is 0.080 N, the temperature of the water is 20 °C, and the temperature of the ice and the aluminum ball is 0 °C.

What is the temperature of the water at the moment the tension in the string becomes zero?

Assume that the thermal equilibrium within the water is established instantly and use the following reference information:

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