0.09m^3 of a fluid at 0.7 bar are compressed reversibly to a pressure of 3.5 bar according to a law pv^n=constant. The fluid is then heated reversibly at a constant volume until the pressure is 4 bar; the specific volume is then 0.5m^3/kg. A reversible expansion according to a law pv^2-constant restores the fluid to its initial state. Calculate the mass of the fluid present, the value of n in the first process and the net work done on or by the fluid in the cycle. Sketch the cycle on the p-V diagram.