$0.3 \mathrm{~g}$ of ethane undergoes combustion at $27^{\circ} \mathrm{C}$ in a bomb calorimeter. The temperature of calorimeter system (including the water) is found to rise by $0.5^{\circ} \mathrm{C}$. The heat evolved during combustion of ethane at constant pressure is ____________ $\mathrm{kJ} ~\mathrm{mol}{ }^{-1}$. (Nearest integer)

[Given : The heat capacity of the calorimeter system is $20 \mathrm{~kJ} \mathrm{~K}^{-1}, \mathrm{R}=8.3 ~\mathrm{JK}^{-1} \mathrm{~mol}^{-1}$.

Assume ideal gas behaviour.

Atomic mass of $\mathrm{C}$ and $\mathrm{H}$ are 12 and $1 \mathrm{~g} \mathrm{~mol}^{-1}$ respectively]