A four-stroke petrol engine develops 30 kW at 2600 rpm. The compression ratio of the engine is 8 and its fuel consumption is 8.4 kg/h with calorific value of 44 MJ/kg. The air consumption of the engine as measured by means of a sharp-edged orifice is 2 m per min. If the piston displacement volume is 2 litres, calculate (a) the volumetric efficiency, (b) the air-fuel ratio, (c) the brake mean effective pressure, (d) the brake thermal efficiency, and (e) the relative efficiency. The ambient temperature air can be taken as 27C, R for air as 287 J/kgK, and y= 1.4. The barometer reads 755 mm of mercury. [LAS, 2006]