Geothermal activity visible on the surface,acute to extreme seismographic readings. typically on the borders of tectonics plates. (Ring of fire)
They are narrower than the ones if the Atlantic and are not covered with thick layers of sediment.
The circle has two forms of equation - General Form and Standard Form. The general form of the equation of the circle would be x^2 + y^2 + Dx + Ey + F = 0. The constants of this equation are D , E and F. The way to use general form is to complete the square and then proceed the equation in standard form. In that way we can identify the radius and center of the given circle.
The correct answer is - Watershed.
The drainage basis are places in which all the water in an area is accumulated and ends up in the same place. The drainage systems are divided by highlands, which can vary from small hills to very high mountains, depending on the topography of the place.
The line on the highland that is separating the drainage systems is called watershed. The watershed is simply a line stretching on the highest parts of a highland, thus having a slope on each side.