Answer
$A=4.39\times10^{-8}m^2$
$l=39.7m$
Work Step by Step
$15.2\Omega=(1.68\times10^{-8}\Omega \cdot m)\frac{l}{A}$
$lA=\frac{0.0155kg}{8900kg/m^3}$
$l=\frac{15.2\Omega A}{1.68\times10^{-8}\Omega \cdot m}$
$\frac{15.2\Omega A^2}{1.68\times10^{-8}\Omega \cdot m}=\frac{0.0155kg}{8900kg/m^3}$
$A=4.39\times10^{-8}m^2$
$l=39.7m$