Given,

Length of wire, l = 1m

Radius of wire, r=0.1mm=0.1×10^-3m

Resistance of the wire, R =100 Ω

Formula used,

The resistivity, ρ, of a wire with cross-sectional area A and length l is expressed as

Where R is the resistance offered by the wire.

Solution,

Firs, we find the area of cross-section of the wire as,

By substituting the value of r, Area becomes

Now substitute all the given values in the expression for resistivity. So, ρ is

So, the resistivity of the material is π×10^-6 Ωm