Explanation:
A. White Dwarf: It is the end stage of a Sun-like star. At the end the red giant star will throw away the outer layers in the form a shell and in the center a hot and bright core will remain. This core consists of carbon and oxygen but the conditions are not suitable to start the fusion of carbon and oxygen.
B. Protostar: It is the initial stage of a star. Here the fuel is available but still the temperature and pressure are not enough to start the nuclear fusion.
C. Main Sequence Star: A star that is fusing Hydrogen in the core to make Helium and releasing the energy in this process. Sun is currently in its main sequence stage. A star spend 90% of its lifetime in main sequence stage.
D. Red Giant Star: In such stars, the hydrogen has been exhausted and only Helium is left. As the core starts contracting under gravity, the conditions are apt for the fusion of Helium to begin. Helium starts fusing to make carbon while in the outer layer Hydrogen to Helium process goes on. As a result the star expands.
The law of conservation of energy states that energy is not created nor destroyed, rather it is only transferred or transmitted from one form to another. Now, the work exerted which is the input is only transformed to move the object which is now becomes the output work. Some are used to move the object, some are converted to other forms. That is why it is never greater than the input energy. Thank you for your question. Please don't hesitate to ask in Brainly your queries.
<span>Fossils are the preserved remains or traces of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous (fossil-containing) rock formations and sedimentary layers (strata) is known as the fossil record</span>
