4.1 1,000 g of water at 20 °C are placed in thermal contact with a heat bath at 80 °C. What is the change in entropy of the total system

(water plus heat bath) when equilibrium has been re-established?

If the 1,000 g of water at 20 °C are heated by successively placing the water into heat baths at 50 °C and 80 °C (waiting each time until equilibrium is reached) what is the entropy change of the total system?

(Specific heat of water = 4.2 J g–1 (°C)–1.)