See the electrical circuit shown in the adjoining figure. Which of the following equations is a correct equation for it?

The figure shows a network of currents. The values of the currents are shown in the figure. What is the value of current $I$ in $A$?

If ${V_{AB}} = 4\,V$ in the given figure,then resistance $X$ will be .............. $\Omega$.

If the resistances are chosen for the circuit shown in the figure in such a way that no current flows through the battery with emf $E_1 = 2 \ V$,the voltage $V_2$ across $R_2$ and the current $I_3$ flowing through $R_3$ are respectively,

$A$ Wheatstone bridge has the resistances $10 \Omega, 10 \Omega, 10 \Omega$ and $30 \Omega$ in its four arms. What resistance joined in parallel to the $30 \Omega$ resistance will bring it to the balanced condition (in $\Omega$)?

Two resistances $R_1 = X \Omega$ and $R_2 = 1 \Omega$ are connected to a wire $AB$ of uniform resistivity,as shown in the figure. The radius of the wire varies linearly along its axis from $0.2 \text{ mm}$ at $A$ to $1 \text{ mm}$ at $B$. $A$ galvanometer $(G)$ connected to the center of the wire,$50 \text{ cm}$ from each end along its axis,shows zero deflection when $A$ and $B$ are connected to a battery. The value of $X$ is: