$A$ hollow sphere of charge does not produce an electric field at any

Charges are uniformly spread on the surface of a conducting sphere. The electric field from the centre of the sphere to a point outside the sphere varies with distance $r$ from the centre as:

Two infinite sheets of uniform charge density $+\sigma$ and $-\sigma$ are parallel to each other as shown in the figure. The electric field is:

An infinite line charge produces a field of $9 \times 10^4 \ NC^{-1}$ at a distance of $2 \ cm$. Its linear charge density is

The figure shows the graph of electric field $E(r)$ versus distance $(r)$ from the center of an object. Therefore,...

Two large,thin metal plates are parallel and close to each other. On their inner faces,the plates have surface charge densities of opposite signs and of magnitude $17.0 \times 10^{-22} \; C/m^2$. What is $E$:
$(a)$ in the outer region of the first plate,
$(b)$ in the outer region of the second plate,and
$(c)$ between the plates?