Answer
$0.12\,\Omega$
Work Step by Step
$R_{Al}=\rho_{Al}\times\frac{l}{A}=0.20\,\Omega$
$R_{Cu}=\rho_{Cu}\times\frac{l}{A}=\frac{R_{Al}}{\rho_{Al}}\times\rho_{Cu}$
$=\frac{0.20\,\Omega}{2.82\times10^{-8}\,\Omega\cdot m}\times1.72\times10^{-8}\,\Omega\cdot m=0.12\,\Omega$
