Consider a reheat-regenerative vapor power cycle with two feedwater heaters. Steam enters the first turbine at 8.0 Mpa, 480oC and expands to 0.7 Mpa. The steam is reheated to 450oC before entering the second turbine, where it expands to the condenser pressure 0.008 Mpa. Steam is extracted from the first turbine at 2 Mpa and fed to closed feed water heater. Feed water leaves the closed heater at 205oC and 8.0 Mpa, and condensate exits as saturated liquid at 2 Mpa. The condensate is trapped into the open feedwater heater. The steam extracted from the second turbine at 0.3 Mpa is also fed into the open feedwater heater, which operates at 0.3 Mpa. The steam exiting the open feedwater heater is saturated liquid at 0.3 Mpa. The net power output is 100 MW. If the isentropic efficiency of the turbines are 90%, please plot the T-S diagram and determine (a) thermal efficiency (b) mass flow rate of the steam entering the first turbine.