The effective resistance between $P$ and $Q$ for the following network is: (in $Omega$)

$(a)$ Given $n$ resistors each of resistance $R,$ how will you combine them to get the $(i)$ maximum $(ii)$ minimum effective resistance? What is the ratio of the maximum to minimum resistance?
$(b)$ Given the resistances of $1\; \Omega, 2\; \Omega, 3\; \Omega,$ how will you combine them to get an equivalent resistance of $(i) \;(11 / 3)\; \Omega,$ $(ii)\;(11 / 5)\; \Omega,$ $(iii)\; 6\;\Omega,$ $(iv)\;(6 / 11)\; \Omega ?$
$(c)$ Determine the equivalent resistance of the networks shown in the figure.

Find out the equivalent resistance between $A$ and $B$.

Each of the resistors shown in the figure has resistance $R.$ Find the equivalent resistance between $A$ and $B :$

$A$ wire of resistance $R$ and length $L$ is cut into $5$ equal parts. If these parts are joined in parallel,then the resultant resistance will be:

Explain the series connection of resistors. Derive the equation for the equivalent resistance $(R_S)$.