An insulated tank of 1m3 volume contains air at 0.1 MPa and 300 K. The tank is connected to a high pressure line in which air at 1 MPa and 600 K flows. The tank is quickly filled with air by opening the valve between the tank and high pressure line. If the final pressure of air in the tank is 1 MPa, determine the mass of air which enters the tank and the entropy change associated with filling process. Take Universal Gas Constant = 8.314 kJ/kg-mol-K