The relation between Seebeck coefficient $S$, thermoelectric power and Peltier coefficient $\pi$ is given by

All the bulbs shown in the given figure marked $1, 2, 3, 4$ and $5$ are identical. The bulb(s) that lights most brightly is 

In the circuit shown in the figure, the currents $i_1$ and $i_2$ are passing through resistances $R_1$ and $R_2$ respectively, $V_1$ and $V_2$ are the respective voltage drops. If current $i$ is passing from $E$ to $F$ and the voltage drop across $EF$ is $V$, then these quantities are related as

For the network shown in figure, the resistance between points $A$ and $B$ will be,