Perform two phase equilibrium calculation with successive substitution method (SSM) for the below five-component system at 390K and selected pressure points (4.42, 5, 5.55 MPa) to determine vapor phase fraction, vapor/liquid phase composition and iteration numbers. Choose either PR or SRK Equation of State (EOS) as the thermodynamic model.
　　C2　　C3　　nC4　　nC5　　nC6
zi　　0.39842　　0.29313　　0.20006　　0.07143　　0.03696