An $n$-type silicon bar $0.1 \mathrm{~cm}$ long and $100 \; \mu \mathrm{m}^{2}$ in cross-sectional area has a majority carrier concentration of $5 \times 1020 / \mathrm{m}^{3}$ and the carrier mobility is $0.13 \mathrm{~m}^{0} / \mathrm{V}-s$ at $300 \mathrm{~K}$. If the charge of an electron is $1.6 \times 10^{-19}$ coulomb, then the resistance of the bar is
- $10^{6} \; \mathrm{ohm}$
- $10^{4} \; \mathrm{ohm}$
- $10^{-1} \; \mathrm{ohm}$
- $10^{-4} \; \mathrm{ohm}$