Table shows electrical resistivity of some substances.

Substance	Silver	Copper	Tungsten	Iron	Mercury	Nichrome
Resistivity	$1.6\times {10}^{-8} \mathrm{\Omega } \mathrm{m}$	$1.62\times {10}^{-8} \mathrm{\Omega } \mathrm{m}$	$5.20\times {10}^{-8} \mathrm{\Omega } \mathrm{m}$	$10.0\times {10}^{-8} \mathrm{\Omega } \mathrm{m}$	$9.4\times {10}^{-8} \mathrm{\Omega } \mathrm{m}$	$100\times {10}^{-6 }\mathrm{\Omega } \mathrm{m}$

Answer the following question in relation to the substances.
Among silver and copper, which one is a better conductor?