The following particulars were obtained in a trial on a four stroke gas engine: Duration of trial = 1 hour, Revolutions = 14000, Number of missed cycle = 500, Net brake load = 1470 N, Mean effective pressure = 7.5 bar, Gas consumption = 20000 liter, L.C.V. of gas at supply conditions = 21 KJ/Liter, Cylinder diameter = 250 mm, Stroke = 400 mm, Effective brake circumferences = 4 m, Compression ratio = 6.5:1 Calculate i) Indicated power ii) Brake power iii) Mechanical efficiency iv) Indicated thermal efficiency