An automobile engine operates at A fuel air ratio of 0.05, volumetric efficiency of 90% and indicated thermal efficiency of 30%. Given that the calorific value of the fuel is 45 MJ/kg and the density of air at intake is 1 kg/m3, the indicated mean effective pressure for the engine is
(a) 6.075 bar (b) 6.75 bar
(c) 67.5 bar (d) 243 bar