The separation between the plates of an isolated charged parallel plate capacitor is increased. Which of the following quantities will change?

Two capacitors of $3 \mu F$ and $6 \mu F$ are connected in series and a potential difference of $900 \ V$ is applied across the combination. They are then disconnected and reconnected in parallel. The potential difference across the combination is

Two parallel plate capacitors $C_1$ and $C_2$ each having capacitance of $10 \mu F$ are individually charged by a $100 \, V$ $D.C.$ source. Capacitor $C_1$ is kept connected to the source and a dielectric slab is inserted between its plates. Capacitor $C_2$ is disconnected from the source and then a dielectric slab is inserted in it. Afterwards,the capacitor $C_1$ is also disconnected from the source and the two capacitors are finally connected in parallel combination. The common potential of the combination will be $......... \, V$. (Assuming dielectric constant $K = 10$)

The charge on any one of the $2\,\mu F$ capacitors and the $1\,\mu F$ capacitor will be given respectively (in $\mu C$) as

The potential of point $A$ is greater than that of point $B$ by $19 \, V$. What is the potential difference in volts across the $3 \, \mu F$ capacitor?

As shown in the figure,the work done in moving a charge $q$ from $A$ to $B$ and from $B$ to $C$ is $2 \ J$ and $-3 \ J$ respectively. The work done in moving the charge from $C$ to $A$ will be ...... $J$.