$A$ uniform wire of length $l$ and radius $r$ has a resistance of $100\, \Omega$. It is recast into a wire of radius $\frac{r}{2}$. The resistance of the new wire will be ............... $\Omega$.

The resistance of a wire is $20 \, \Omega$. It is stretched such that its length becomes three times its original length. The new resistance of the wire will be ............. $ \Omega$.

$A$ wire of resistance $4 \,\Omega$ is stretched to twice its original length. The resistance of the stretched wire would be ........... $\Omega$.

$A$ uniform wire of resistance $R$ is uniformly compressed along its length,until its radius becomes $n$ times the original radius. Now,the resistance of the wire becomes:

Find the resistance of a cube of edge $60 \text{ cm}$,made of a material of specific resistance $60 \times 10^{-8} \Omega \text{ m}$.

$A$ rectangular parallelopiped is measured as $1\,cm \times 1\,cm \times 100\,cm$. If its specific resistance is $3 \times 10^{-7}\,\Omega\,m$,then the resistance between its two opposite rectangular faces (as shown in the figure) will be $.......... \times 10^{-7} \Omega$.