Answer
0.536 Ω
Work Step by Step
Given: Area A=$ 56.0 cm^{2}= 56.0\times10^{-4}m^{2}$
Length l= 10.0 km= $10.0\times10^{3}m$
Resistivity $\rho= 3.00\times10^{-7}Ωm$
Using the relation $R=\frac{\rho l}{A}$, we have
$R= \frac{3.00\times10^{-7}Ωm\times10.0\times10^{3}m}{56.0\times10^{-4}m^{2}}=0.536 Ω$
