my starting of system is 100 bar and 260 degree C. the saturation temperature for 100 bar is 311 degree C. so in order to find my enthalpy and entropy, i need to find x, dryness fraction. but my equation have 2 unknowns. how do I calculate availability? availability = (h-h0) -T0(s-s0) s = sf + xsfg have 2 unknowns. how do i compute s and h in order to compute availability?