A wire of resistance $32 \Omega$ is melted and redrawn into wire of half its original length. Find the resistance of the new wire.

Two copper wires $\mathrm{A}$ and $\mathrm{B}$ of equal masses are taken. The length of $\mathrm{A}$ is double the length of  $\mathrm{B}$. If the resistance of the wire $\mathrm{B}$. If the resistance of wire A is $160\Omega$, then calculate the resistance of wire B.

A rectangular block of iron has dimensions $1.2 \mathrm{cm} \times 1.2 \mathrm{cm} \times 15 \mathrm{cm}$. Compute the resistance of the block between the two square ends. The specific resistance of iron at room temperature is $9.68 \times {10}^{-8 }\mathrm{\Omega } \mathrm{m}$.