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 SCIENCE FACTS. Introduction. When the star that we call our Sun condensed out of a swirling cloud of hot interstellar gas, some material remained in orbit around the newly forming star. That orbiting material consisted of hot chunks of rock and frozen liquids called planetisimals.