Can someone please help me with this page. I don’t understand it at all

Which system of units is used by only a small number of countries in the world, including the u.s.

One kind of e-book display consists of millions of very small spheres that float in a thin fluid layer between two conducting transparent plates. each sphere is black on one side and white on the other, and possesses an electric dipole moment directed from the white side to the black. when an electric field is applied between the plates, the spheres rotate so that their dipole moment lines up with the field. depending on the fields direction, either the black or the white sides of th espheres can be made visible.the dipole moment of the spheres can be modeled as two opposite charges of magnitude 3.5 x 10^-15 c, separated by a distancce of 100 micrometers (um). what is the maximum possible torque on a sphere if the electric field between the transparent plates is 4.0 x 10^5 n/c

What is required to bring about a phase change 1.an increase or decrease in pressure 2.an increase or decrease in energy 3.an increase in energy only 3.a decrease in energy only