What will be the equivalent resistance between the two points $A$ and $D$ in the given circuit (in $\Omega$)? (All resistors are $10 \ \Omega$ each.)

$A$ student was trying to construct the circuit shown in the figure below marked $(a)$,but ended up constructing the circuit marked $(b)$. Realising her mistake,she corrected the circuit,but to her surprise,the output voltage (across $R$) did not change. The value of resistance $R$ is ............ $\Omega$

In the given circuit,the potential at the point $B$ with respect to the point $A$ is (in $\text{V}$):

The potential difference $(V_A - V_B)$ between the points $A$ and $B$ in the given part of the circuit is:

$A$ heater is rated $100\ W, 200\ V$. It is cut into two equal parts. Both parts are connected in parallel to the same $200\ V$ source. The energy released per second in this new combination is ............. $W$.

$A$ galvanometer of resistance $G$ is connected in a circuit. Now,a resistance $R$ is connected in series with the galvanometer. To keep the main current in the circuit unchanged,the resistance $S$ to be put in parallel with the series combination of $G$ and $R$ is: