If the kinetic energy of electron is $18.2 \times 10^{-25} \mathrm{~J}$, its de Broglie wavelength in $\mathrm{nm}$ is : (mass of electron $\left.=9.1 \times 10^{-31} \mathrm{~kg} ; \mathrm{h}=6.626 \times 10^{-34} \mathrm{~J} \mathrm{~s}\right)$