2. A perfectly insulated, rigid tank with a volume of 0.2 m' contains a perfect gas which has a molar mass (m) 18 kg/kmol and a ratio of specific heats of 1.45 Initially the pressure and temperature in the tank are 9 bar and 320 K respectively. A fan inside the tank is spun at 3600 rev/min for 20 seconds. The torque required to turn the fan is 30 N m. a) Calculate the following: i) The gas constant Rg ii) cp, and cy for the gas iii) The mass of the gas in the tank. iv) The work input to the gas from the fan. v) The final temperature of the gas. vi) The increase in entropy of the gas [Hint: Entropy S = mRInV + mCylnT] [15 m