A steel casting at a temperature of \(725 \mathrm{~K}\) and weighing \(35 \mathrm{~kg}\) is quenched in \(150 \mathrm{~kg}\) oil at \(275 \mathrm{~K}\). If there is no heat losses, determine the change in entropy. The specific heat \(\left(C_{P}\right)\) of steel is \(0.88 \mathrm{~kJ} / \mathrm{kg}-\mathrm{K}\) and that of oil is \(2.5 \mathrm{~kJ} / \mathrm{kg}-\mathrm{K}\).