A parallel plate capacitor is made up of stair like structure with a plate area A of each stair and that is connected with a wire of length $b$, as shown in the figure. The capacitance of the arrangement is $\frac{x}{15}\frac{{\epsilon }_0 A}{ b}$, The value of $x$ is _____ .

Statement-I : A point charge is brought in an electric field. The value of electric field at a point near to the charge may increase if the charge is positive.

Statement-II : An electric dipole is placed in a non-uniform electric field. The net electric force on the dipole will not be zero.

The three charges $\frac{q}{2},q$ and $\frac{q}{2}$ are placed at the corners $A,D$ and $C$ of a square of side $a$ as shown in figure. The magnitude of electric field $\left(E\right)$ at the corner $B$ of the square, is 

A capacitor $C_1$ of capacitance $5 \mu \mathrm{F}$ is charged to a potential of $30 \mathrm{V}$ using a battery. The battery is then removed and the charged capacitor is connected to an uncharged capacitor $C_2$ of capacitance $10 \mu \mathrm{F}$ as shown in figure. When the switch is closed charge flows between the capacitors. At equilibrium, the charge on the capacitor $C_2$ is _____ $\mu \mathrm{C}$.