QQQ has huge tech exposure, but it is not a 'tech fund' in the pure sense either. The fund's arcane weighting rules further distance it from anything close to plain vanilla large-cap or pure-play tech coverage.
During the time when Earth was forming and was in a molten state, heavy materials like iron and nickel sank to the center of the Earth's mass and lighter materials floated to the surface of the mass. The very center of what we call the core, is solid in the middle because of the increased pressure in that region.
Earth in its infancy was probably largely covered by extremely hot, molten rock. heavy substances, probably mainly iron and nickel, sank towards the centre of the Earth to form a dense, solid inner core. movements in the liquid outer core generate electricity. this electricity creates the Earths magnetic properties.