The mass of an insulated 0.6 m3 steel tank is 20 kg. the steel has a specific heat of 0.46 kj/kg·k. the tank is placed in a room where the surrounding air is 21°c and 101.3 kpa. after the tank is evacuated to 7 kpa and 21°c, a valve is suddenly opened, allowing the tank to fill with room air. the air enters the tank in a well mixed, turbulent condition. find the air temperature inside the tank after filling and after the gas and tank have reached thermal equilibrium, but before any heat loss from the tank to the room occurs.