The equivalent capacitance between points $A$ and $B$ as shown in the figure is:

When two identical capacitors are in series,they have $3\,\mu F$ capacitance,and when in parallel,they have $12\,\mu F$ capacitance. What is the capacitance of each capacitor in $\mu F$?

Two capacitors $C_1 = 2 \ \mu F$ and $C_2 = 3 \ \mu F$ are connected in series between points $A$ and $C$. The potential at point $A$ is $40 \ V$ and the potential at point $C$ is $10 \ V$. Find the potential at point $B$ (between the two capacitors). (in $V$)

Two capacitors of capacity $4 \mu F$ and $6 \mu F$ are connected in series to a $500 \ V$ battery. The potential difference across the $4 \mu F$ capacitor is: (in $V$)

Find the equivalent capacitance between two points $A$ and $B$ for the given circuit. (Capacitance of each capacitor is $C = 3 \mu F$.) (in $\mu F$)

Four capacitors are connected as shown in the figure. If $C_1, C_2, C_3$ and $C_4$ are in the ratio of $1: 2: 3: 4$,then the ratio of the charges on the capacitors $C_2$ and $C_4$ is