The correct sequence of events is : C,D,B,A.
Iron rich magma in the earth's core heats up because of radiation and the pressure exerted by the other layers of the earth. This heat in the crust trigger convection currents in the mantle. The magma closest to the core will be hotter and therefore less dense than other layers. Being less dense the layer will rise towards the crust, eventually becoming cooler and sinking back down in a circular motion.
The continued circular motion creates electric currents which then generates the magnetic field.
Answer:
There are basically 4 components of Biosphere.
Explanation:
Biosphere is the collection of all ecosystems on earth and their interactions with each other. The Biosphere of earth consists the following components,
1. The Biota
All the living organisms including animals, plants, insects and bacteria is called the Biota.
2. Geosphere
Geosphere is the surface of biosphere that is composed of soil, rocks, mountains etc.
3. Hydrosphere
The hydrosphere includes all the water bodies like ocean, rivers, streams and lakes.
4. Atmosphere
Atmosphere is the climate that describes about the temperature, humidity, wind and rain fall in Biosphere.
A very large star of high luminosity and low surface temperature. Red giants are thought to be in a late stage of evolution when no hydrogen remains in the core to fuel nuclear fusion.
Its B. <span>Australopithecus africanus, Homo erectus, Homo neanderthalensis</span>