An arbitrary surface encloses a dipole. What is the electric flux through this surface?

Draw the electric field lines of a positive point charge.

If the total charge enclosed by a surface is zero,does it imply that the electric field everywhere on the surface is zero? Conversely,if the electric field everywhere on a surface is zero,does it imply that the net charge inside is zero?

$A$ hollow cylinder has a charge $q$ inside it. If $\phi$ is the electric flux in units of $\text{V}\cdot\text{m}$ associated with the curved surface $B$, what is the flux linked with the plane surface $A$ in units of $\text{V}\cdot\text{m}$?

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

$A$ rectangular surface of sides $10 \,cm$ and $15 \,cm$ is placed inside a uniform electric field of $25 \,V/m$,such that the surface makes an angle of $30^{\circ}$ with the direction of the electric field. Find the flux of the electric field through the rectangular surface in $Nm^2/C$.