Electrical resistivity of a given metallic wire depends upon

Identify the circuit in which the electrical components have been properly connected.

What is the minimum resistance which can be made using five resistors each of $\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$5$}\right.$?

The proper representation of the series combination of cells obtaining maximum potential is 

Which of the following represents voltage?

A cylindrical conductor of length $l$ and uniform area of cross-section $A$ has resistance $R$. Another conductor of length $2l$ and resistance $R$ of the same material has area of cross-section

A student carries out an experiment and plots the $V$-$I$ graph of three samples of nichrome wire with resistances $R_1,R_2 \mathrm{and} {\mathrm{R}}_3$ respectively. Which of the following is true?