There are currently only 13 members of the Senate who served in the military. In all, 97 members of the next session of Congress will have served in the U.S. military. That means less than 18 percent of the new congressional delegation served in the armed forces.
the layer of the earth resposible for the earths magnetic field is the core which consists of the liquid core/outer core and the solid core/inner core.
Another amazing attribute of the earth are the magnetic poles and their fields. The core of the earth produces a field of magnetic energy which surrounds the planet much the same way as the magnetic field of a common bar magnet. The magnetic north allows the needle on a compass to point towards that direction.