Chapter 27 - Current and Resistance - Exercises and Problems - Page 763: 32

$R = 4.0\times 10^3~\Omega$

Note that: $~\rho = \frac{1}{\sigma}$ We can find the resistance: $R = \frac{\rho~L}{A}$ $R = \frac{L}{\sigma~A}$ $R = \frac{L}{\sigma~\pi~r^2}$ $R = \frac{0.20~m}{(0.63~S/m)(\pi)~(0.50\times 10^{-2}~m)^2}$ $R = 4.0\times 10^3~\Omega$