2 2 points 1kg of nitrogen (molar mass 28kg k-1 mol-1) is compressed reversibly and isothermally from 1.01 bar, 20C to 4.2bar. The specific work done is: (Assume nitrogen to be a perfect gas with Specific gas constant R=0.297 kJ kg K-) w=248kJ kg- w = 124kJ kg-1 w = -124kJ kg-1 w = 62kJ kg-1 w = 200kJ kg-1 E R