In a gas turbine plant, air at 10oC and 1.0 bar is compressed to 12 bar with isentropic efficiency of 80%. The air is heated first in the regenerator and then in the combustion chamber till its temperature is raised to 1400oC, and during this process the pressure falls by 0.2 bar. The air is then expanded in the turbine, and then passes through the regenerator, which has an effectiveness of 0.75 and causes a pressure drop of 0.2 bar. Isentropic efficiency of the turbine is 85% . Determine the thermal efficiency of the plant. Assume addition of heat at constant pressure.