Answer
$\rho = 10.6\times 10^{-8}~\Omega\cdot m$
Work Step by Step
We can find the resistivity:
$R = \frac{\rho~L}{A}$
$\rho = \frac{R~A}{L}$
$\rho = \frac{R~\pi~r^2}{L}$
$\rho = \frac{(15.0\times 10^{-3}~\Omega)~(\pi)~(3.00\times 10^{-3}~m)^2}{4.00~m}$
$\rho = 10.6\times 10^{-8}~\Omega\cdot m$
