Draw a landscape sketch of the area and show physical and human features. Describe the relief and vegetation of the area shown. Describe the economic activities that can be seen. Explain the relationship between the physical environment and how they can be seen to earn a living.

b)

Step 1: Nature of field lines for a positive point charge.
The field lines originate from the positive point charge and propagate radially outward to infinity in all directions. They are straight lines.

Step 2: Density variation.
The density of field lines is highest near the charge and decreases with distance, as $E \propto \frac{1}{r^2}$.

Step 3: For negative point charge.
Field lines terminate radially on the negative point charge from infinity.

Sketch description:
In a 2D cross-section, straight arrows radiate symmetrically outward from a central point (the charge), denser near the center.

c)

Step 1: Definition.
Equipotential surfaces are surfaces of constant electric potential $V$. For an electric dipole (+q and -q separated by distance $d$), $V(r) = \frac{1}{4\pi\epsilon_0} \frac{p \cdot \hat{r}}{r^2}$, where $\mathbf{p} = q\mathbf{d}$.

Step 2: Location of dipole.
The zero-potential equipotential surface ($V=0$) is the perpendicular bisector plane through the midpoint of the dipole (equatorial plane, where $\theta = 90^\circ$, $\cos\theta = 0$). The midpoint of the dipole lies on this $V=0$ surface. The charges themselves are not on any finite equipotential (potential diverges there).

Step 3: Shape near dipole.
Close to the dipole, equipotential surfaces are distorted, nearly spherical around each charge but deformed by the presence of the other charge. They are perpendicular to field lines everywhere.

Step 4: Change with distance.
With increasing distance $r \gg d$ from the dipole, equipotential surfaces become larger, more circular (approaching spheres centered at the dipole's midpoint), and sparser due to $V \propto 1/r^2$.

Sketch description:
In the meridional plane (containing dipole axis): Curves symmetric about the axis, bulging outward along the axis and pinched at equatorial plane. Label dipole (+q, -q) on axis between curves. Near: tight curves around charges; far: large nearly-circular arcs. The equatorial line is straight horizontal $V=0$.