What can be said about the electric charge if the electric flux associated with a closed loop (surface) is zero?

$A$ uniformly charged conducting sphere of diameter $3.5 \ cm$ has a surface charge density of $20 \ \mu C \ m^{-2}$. The total electric flux leaving the surface of the sphere is nearly:
[permittivity of free space,$\epsilon_0 = 8.85 \times 10^{-12} \ SI \ unit$]

In a region,the intensity of an electric field is given by $E = 2i + 3j + k$ in $NC^{-1}$. The electric flux through a surface $S = 10i \ m^2$ in the region is

Two concentric spherical surfaces $P_1$ and $P_2$ enclose charges $\frac{Q}{2}$ and $4Q$ as shown in the figure. If $\phi_1$ and $\phi_2$ are the electric fluxes linked with the surfaces $P_1$ and $P_2$ respectively,then:

$A$ large charged plane having surface charge density $4.9 \times 10^{-6} \text{ C m}^{-2}$ lies in the $x-y$ plane. $A$ circular plane of radius $1 \text{ cm}$ is lying completely in the region where $x, y$ and $z$ coordinates are all positive. When the plane's normal makes an angle $60^{\circ}$ with the $z$-axis,the electric flux through the circular plane is (Given: $\frac{1}{4 \pi \varepsilon_0} = 9 \times 10^9 \text{ N m}^2 \text{ C}^{-2}$)

What is the electric flux for Gaussian surface $A$ that encloses the charged particles in free space? [Given: $q_1 = -14 \text{ nC}, q_2 = 78.85 \text{ nC}, q_3 = -56 \text{ nC}$]