A wire with cross-sectional area $5.0 \times 10^{-6}\,\text{m}^2$ is constructed from a metal whose resistivity is $50 \times 10^{-8}\,\Omega\,\text{m}$. The potential difference across the wire is $6.0\,\text{V}$ and the current flowing through it is $3.0\,\text{A}$. What is the wire's length?
- A$0.050\,\text{m}$
- B$0.20\,\text{m}$
- C$5.0\,\text{m}$
- D$20\,\text{m}$