Approximately how long should it take 9.8 kg of ice at 0C to melt when it is placed in a carefully sealed Styrofoam ice chest of dimensions 25 cm 35

Approximately how long should it take 9.8 kg of ice at 0∘C to melt when it is placed in a carefully sealed Styrofoam ice chest of dimensions 25 cm × 35 cm × 55 cm whose walls are 1.3 cm thick? Assume that the conductivity of Styrofoam is double that of air and that the outside temperature is 29 ∘C.

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