If the Wheatstone bridge with four resistors $R_1, R_2, R_3$ and $R_4$ is balanced,then the correct expression is

Two batteries $V_1$ and $V_2$ are connected to three resistors as shown below. If $V_1=2 \,V$ and $V_2=0 \,V$,then the current $I=3 \,mA$. If $V_1=0 \,V$ and $V_2=4 \,V$,then the current $I=4 \,mA$. Now,if $V_1=10 \,V$ and $V_2=10 \,V$,then the current $I$ will be ............ $\,mA$.

Four resistors are connected as shown in the figure. $A$ $6\,V$ battery of negligible resistance is connected across terminals $A$ and $C$. The potential difference across terminals $B$ and $D$ will be ............. $V$.

Calculate the equivalent resistance between $A$ and $B$.

For the given circuit,the reading of the ammeter in amperes is........

Which of the following statements is false?