The average translational kinetic energy of $\mathrm{N}_2$ gas molecules at $\_\_\_\_$ ${ }^{\circ} \mathrm{C}$ becomes equal to the K.E. of an electron accelerated from rest through a potential difference of 0.1 volt. (Given $\mathrm{k}_{\mathrm{B}}=1.38 \times \left.10^{-23} \mathrm{~J} / \mathrm{K}\right)$ (Fill the nearest integer)