The following data are known for a four-cylinder four-stroke petrol engine: cylinder dimensions: 11 cm bore and 13 cm stroke, engine speed: 2250 rpm, brake power: 50 kW, friction power: 15 kW, fuel consumption rate: 10.5 kg/h, calorific value of fuel: 50,000 kJ/kg, air inhalation rate: 300 kg/h, and ambient condition: 15C, 1.03 bar. Estimate (a) brake mean effective pressure, (b) volumetric efficiency, (c) brake thermal efficiency, and (d) mechanical efficiency. [IES, 2008]