) 12 2 Question No. 42 27 libh oftu- keyft One pound mass of air initially occupyinga vurime 60.4 ft at a pressure of 1000 lbf/in expands in a piston-cylinder assembly isothermally and without irreversibility until the volume is 2 ft Using the van der Waals equation of state, determine the: a) temperature, in R. 14/6] b) final pressure, in lbf/in. [4/6] c) work developed in the process, in Btu. 14/6] d) Comment on the work sign obtained in part c. [ 0/2] 18.314