A thin spherical shell of the radius $R$ has a charge $Q$ spread uniformly over its surface. Which of the following graphs most closely represents the electric field $E\left(r\right)$ produced by the shell in the range $0\le r<\infty$, where $r$ is the distance from the centre of the shell?

Statement-$1$: For a charged particle moving from point $P$ to point $Q$, the net-work done by an electrostatic field on the particle is independent of the path connecting point $P$ to point $Q$.

Statement-$2$: The net work done by a conservative force on an object moving along a closed loop is zero.

A thin semi-circular ring of the radius $r$ has a positive charge $q$ distributed uniformly over it. The net field $E$ at the centre $O$ is

Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle of $30°$ with each other. When suspended in a liquid of density $0.8 \mathrm{g} {\mathrm{cm}}^{–3}$, the angle remains the same. If the density of the material of the sphere is $1.6 \mathrm{g} {\mathrm{cm}}^{–3}$, the dielectric constant of the liquid is