Given data m = 1 kg p = 15 bar = 1500 kPa Tsup = 400° C = 673 K x = 0.9Cps = 2.1 kJ / kg K To Find: usup = ? , uwet = ?From steam table at 15 bar, We have, ts = 198.3°C = 471.3 K hf = 844.7 kJ/kg hfg = 1945.2 kJ/kg hg = 2789.9 kJ/kg vg = 0.1317 m3/kg Now, vsupTsup = vgTs vsup = vg × TsupTsvsup= 0.1317 × 673 471.3 vsup = 0.188 m3/kgNow, hsup = hg + Cps ( Tsup - Ts ) hsup = 2789.9 + 2.1 ( 673 - 471.3 )hsup = 3213.47 kJ/kgNow, usup = hsup - pvsup usup = 3213.47 - 1500 × 0.188usup = 2913.47 kJ/kgNow, uwet = hwet - pvwet uwet = ( hf + x hfg ) - p ( x vg )uwet = ( 844 + 0.9 × 1945.2 ) - 1500 ( 0.9 × 0.1317 )uwet = 2417.59 kJ / kg