Electric field lines of force of a positive point charge are

$A$ charge $Q$ is enclosed by a Gaussian surface of radius $R$. If the radius is doubled,then the outward electric flux will

$A$ uniformly charged conducting sphere of $2.4\; m$ diameter has a surface charge density of $80.0\; \mu C/m^2$.
$(a)$ Find the charge on the sphere.
$(b)$ What is the total electric flux leaving the surface of the sphere?

Consider a region in free space bounded by the surfaces of an imaginary cube having sides of length $a$ as shown in the figure. $A$ charge $+Q$ is placed at the centre $O$ of the cube. $P$ is a point outside the cube such that the line $OP$ perpendicularly intersects the surface $ABCD$ at $R$, and $OR = RP = a/2$. $A$ charge $+Q$ is also placed at point $P$. What is the total electric flux through the five faces of the cube other than $ABCD$?

It is not convenient to use a spherical Gaussian surface to find the electric field due to an electric dipole using Gauss's theorem because

Consider three point charges $-2Q$, $Q$ and $-Q$ and three surfaces $S_1$, $S_2$ and $S_3$. Match the entries of List-$I$ with that of List-$II$ using Gauss's Law.

List-$I$	List-$II$
$(a)$ Net flux through $S_1$	$(i)$ $\frac{-2Q}{\epsilon_0}$
$(b)$ Net flux through $S_2$	(ii) $\frac{-Q}{\epsilon_0}$
$(c)$ Net flux through $S_3$	(iii) Zero