A six-cylinder, four-stroke petrol engine develops \(40 \mathrm{~kW}\) when running at \(3000 \mathrm{rpm}\). The volumetric efficiency at NTP is \(85 \%\). Indicated thermal efficiency is \(25 \%\). The A/F ratio of the mixture supplied is \(15: 1 . \mathrm{CV}\) of fuel used \(=41 \mathrm{MJ} / \mathrm{kg}\). Assume stroke \(/\) bore ratio \(=1.25\).

Calculate the bore and stroke of the engine.