The equivalent resistance between the points $A$ and $B$ is:

There are $8$ equal resistances $R$. Two are connected in parallel,and such four groups are connected in series. The total resistance of the system will be:

Eight resistances each of resistance $5\,\Omega$ are connected in the circuit as shown in the figure. The equivalent resistance between $A$ and $B$ is

The equivalent resistance between $A$ and $B$ for the mesh shown in the figure is ......... $\Omega$.

Two wires of same metal have the same length but their cross-sections are in the ratio $3:1$. They are joined in series. The resistance of the thicker wire is $10\,\Omega$. The total resistance of the combination will be ............. $\Omega$.

Eight copper wires of length $l$ and diameter $d$ are joined in parallel to form a single composite conductor of resistance $R$. If a single copper wire of length $2\,l$ has the same resistance $R$,then its diameter will be $.....d$.