Three samples of 100 g of water (samples I, II and III), initially kept at 1 atm pressure and 298 K were given the following treatments. Sample I was heated to 320 K and cooled to 298 K Sample II was heated to 300 K , cooled to 273 K and heated to 298 K Sample III was heated to 373 K and cooled to 298 K At the end of these processes, the internal energy of