To 100.0 g water at 25.00 ºC in a well-insulated container is added a block of aluminum initially at — Thermodynamics Chemistry Question

To 100.0 g water at 25.00 ºC in a well-insulated container is added a block of aluminum initially at 100.0 ºC. The temperature of the water once the system reaches thermal equilibrium is 28.00 ºC. What is the mass of the aluminum block? (The specific heat capacity of Al is 0.900 J g–1 K–1.)