binary vapor cycle

1. Give the reasons why mercury is a suitable working fluid for the topping cycle in a binary vapor cycle, and not for the bottoming cycle.
2. The net power produced by a combined gas turbine-vapor cycle power plant is 40MW. Steam leaves the heat exchanger at 6000 kPa and 427°C (700.15K). Incoming air into the compressor of the gas turbine system is at 25°C (298.15K) and 100 kPa and it leaves the compressor at 1100 kPa. The gas leaves the cycle at 160°C (433.15K). Heat is added at constant pressure, after which the air leaves the combustor at 1177°C (1450.15K). Both the gas turbine cycle and the Rankine cycle are ideal. Compute the flow rates in each cycle, the overall thermal efficiency, and the availability utilization of the gas turbine exhaust. The condenser pressure of the Rankine cycle is 7 kPa. The environment is at 25°C (298.15K). Assume that air is the working fluid in the gas turbine cycle, thus neglecting the mass of the fuel.