Four plates of equal area $A$ are separated by equal distances $d$ and are arranged as shown in the figure. The equivalent capacity is

Two capacitors of capacities $2 \mu F$ and $4 \mu F$ are connected in parallel. $A$ third capacitor of $6 \mu F$ capacity is connected in series with this combination. $A$ battery of $12 \text{ V}$ is connected across this combination. The charge on the $2 \mu F$ capacitor is: (in $\mu C$)

The potential difference across the $4 \mu F$ capacitor in series with the parallel combination in the following circuit is: (in $V$)

Four capacitors of equal capacity have an equivalent capacitance $C_{1}$ when connected in series and an equivalent capacitance $C_{2}$ when connected in parallel. The ratio $\frac{C_{2}}{C_{1}}$ is:

In the given network, the value of $C$, so that an equivalent capacitance between points $A$ and $B$ is $3 \mu F$, is

The effective capacitance between points $X$ and $Y$ in the figure shown below is. (Assume all the capacitors are $4 \mu F$ each) (in $\mu F$)