Equipotential surfaces associated with an electric field which is increasing in magnitude along the $x$-direction are

Which of the following figure shows the correct equipotential surfaces of a system of two positive charges?

What is an equipotential surface ? Draw an equipotential surfaces for a

$(1)$ single point charge

$(2)$ charge $+ \mathrm{q}$ and $- \mathrm{q}$ at few distance (dipole)

$(3)$ two $+ \mathrm{q}$ charges at few distance

$(4)$ uniform electric field.

Describe schematically the equipotential surfaces corresponding to

$(a)$ a constant electric field in the $z-$direction,

$(b)$ a field that uniformly increases in magnitude but remains in a constant (say, $z$) direction,

$(c)$ a single positive charge at the origin, and

$(d)$ a uniform grid consisting of long equally spaced parallel charged wires in a plane

Electric field is always ...... to the equipotential surface at every point. (Fill in the gap)

Assertion : Two equipotential surfaces cannot cut each other.

Reason : Two equipotential surfaces are parallel to each other.