A 28 g block of ice is cooled to −86◦C. It is added to 513 g of water in an 67 g copper calorimeter at a temperature of 21◦C. Find the final temperature. The specific
heat of copper is 387 J/kg ·◦C and of ice is 2090 J/kg ·◦C . The latent heat of fusion of water is 3.33 × 10^5 J/kg and its specific heat is 4186 J/kg · C.
Answer in units of ◦C.