Total $emf$ produced in a thermocouple does not depend on

Four lamps are connected as shown in the figure. When switch $S_2$ is open and switch $S_1$ is at position $2$,lamp $b$ is the brightest,and lamps $c$ and $d$ are the dimmest and have the same brightness. Now,if $S_2$ is closed and $S_1$ is at position $1$,what is the sequence of brightness of the lamps (starting from the brightest)?

The battery shown in the figure has an $e.m.f.$ $E$ and internal resistance $r$. The current in the circuit can be varied by sliding the contact $J$. If at any instant the current flowing through the circuit is $I$,the potential difference between the terminals of the cell is $V$,and the thermal power generated in the cell is equal to $\eta$ fraction of the total electrical power generated in it,then which of the following graphs is correct?

$A$ battery of $e.m.f.$ $E$ is connected in series with a resistor $R$ and a voltmeter $V$. An ammeter $A$ is connected in parallel with the battery. Then:

When a $CuSO_4$ cell and an $AgNO_3$ cell are connected in series and a current is passed through them,if $1 \, mg$ of copper is deposited in the first cell,how much silver (in $mg$) will be deposited in the second cell? $(A_{Cu} = 63.57, A_{Ag} = 107.88)$

$A$ thermocouple produces $200\,\mu V$ between $0\,^oC$ and $100\,^oC$. If it produces $64\,\mu V$ and $76\,\mu V$ for temperature ranges $(0\,^oC - 32\,^oC)$ and $(32\,^oC - 70\,^oC)$ respectively,then the thermo $emf$ produced between $70\,^oC$ and $100\,^oC$ will be ........... $\mu V$.