A gas undergoes an adiabatic process and an isothermal process. The two processes are plotted on a p-V diagram. The resulting curves intersect at a point P. Tangents are drawn to the two curves at P. These make angles of ${135}^o$and ${121}^o$with the positive V-axis. The gas is likely to be [Given $\tan {59}^0$ =1.67] [p = pressure, V=volume of gas]