The value of specific heat for copper is 390 J/kg∘C , for aluminum is 900 J/kg^∘C , and for water is 4186 J/kg^∘C, What will be the equilibrium temperature when a 275 g block of copper at 255 ^∘C is placed in a 145 g aluminum calorimeter cup containing 855 g of water at 13.0 ^∘C ?