The number of electric lines that emerge from a finite charge $+q$ is . . . . . . .

$A$ few electric field lines for a system of two charges $Q_1$ and $Q_2$ fixed at two different points on the $x$-axis are shown in the figure. These lines suggest that:-

If a charge $q$ is placed at the centre of the flat surface of a closed hemispherical non-conducting surface,what is the total electric flux passing through the flat surface?

$A$ charge $q$ is placed at the centre of the open end of a cylindrical vessel. The flux of the electric field through the surface of the vessel is:

Five point charges $\frac{1}{\pi}, \frac{2}{\pi}, \frac{3}{\pi}, \frac{4}{\pi}$ and $\frac{-5}{\pi} \ nC$ are located inside a pyramid. The total electric flux through the surface of the pyramid is

$A$ charge of $1 \,C$ is located at the centre of a sphere of radius $10 \,cm$ and a cube of side $20 \,cm$. The ratio of outgoing flux from the sphere and cube will be