2. The four inner planets have slower orbits, slower spin, no rings, and they are made of rock and metal. The four outer planets have faster orbits and spins, a composition of gases and liquids, numerous moons, and rings. The outer planets are made of hydrogen and helium, so they are called gas giants.
3. Earth formed about 4.6 billion years ago during the birth of our solar system. ... During the next major phase of earth's formation cooling and differentiation of the Earth's layers occurred. Dense materials sank to the center, forming an iron-nickel rich core. Lighter buoyant silicate-rich magma rose to the surface.
4. Instead of using CAT-scans and X-rays to see the center of the Earth, researchers use waves emitted by earthquakes to get a sense of the planet's innards. ... These tests are what allowed scientists to see that the core of the Earth is broken into three layers all with slightly different structures
5. Scientists believe Earth's magnetic field results from movements of molten iron and nickel within its liquid outer core. ... Earth's magnetic field is essential for life on Earth
Hope this helps you :).
(Sorry it’s so long btw)