The equivalent capacitance of three capacitors of capacitance $C_1, C_2$ and $C_3$ connected in parallel is $12$ units and the product $C_1. C_2. C_3=48.$ When the capacitors $C_1$ and $C_2$ are connected in parallel the equivalent capacitance is $6$ units. Then the capacitance are-

When a potential difference of ${10}^3 \mathrm{V}$ is applied between $\mathrm{A}$ and $\mathrm{B}\text{,}$ a charge of $0.75 \mathrm{mC}$ is stored in the system of capacitors. The value of $C$ is $\left(\mathrm{\mu F}\right)$

What is effective capacitance between points $X$ and $Y$ in fig.-

The capacitors $A$ and $B$ are connected in series with a battery as shown in the figure. When the switch $S$ is closed and the two capacitors get charged fully, then 

The equivalent capacitance in the circuit shown in fig. will be-