What are the two lines that divide the earth into the northern and southern hemispheres and the eastern and western hemispheres?

Any circle drawn around the Earth divides it into two equal halves called hemispheres. There are generally considered to be four hemispheres: Northern, Southern, Eastern, and Western. The Equator, or line of 0 degrees latitude, divides the Earth into the Northern and Southern hemispheres.

Lol why dont you actually do the work instead of have people do it for you. jk i do it too lol

The "highest" point is a single point. 
there can't be more than one "highest" point.
it's not possible for every point on a line to be the "highest" one.