B. Main sequence
C. Nebula
D. Protostar
The correct answer is D. Protostar.
Nuclear fusion in a star's lifecycle begins during the protostar stage. This is when the temperature and pressure of the protostar ignite nuclear fusion, transitioning into a main sequence star.
In the life cycle of a star, nuclear fusion begins when the star has reached the protostar stage. The initial stage in the development of a star is the nebula, which is a cloud of dust and gas. Over time, the nebula's materials collapse under gravity to form a hot core known as a protostar.
When the protostar's temperature and pressure rises, it triggers nuclear fusion and the star begins turning hydrogen into helium.
This marks the transition from a protostar to a main sequence star, which is the stage of stable nuclear fusion.
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Answer:what is the role of of geologist in the petroleum industry
A. Stay with the drillers to examine rocks and fossils brought to the surface.
B. Chart information on a well log
C. Calculate the distance and direction of movement of the lost vein of ore
D. locate environment in which the petroleum forms
Correct option. Is D locate environment in which petroleum forms
Explanation:
Petroleum geologists are usually linked to the actual discovery of oil and the identification of possible oil deposits or leads. It can be a very labor-intensive task involving several different fields of science and elaborate equipment. Petroleum
geologists look at the structural and
sedimentary aspects of the stratum/strata to identify possible oil traps
Answer: D locate environment in which the petroleum forms
Explanation:
Principles of relative dating
Uniformitarianism. ...
Intrusive relationships. ...
Cross-cutting relationships. ...
Inclusions and components. ...
Original horizontality. ...
Superposition. ...
Faunal succession. ...
Lateral continuity.
https://en.wikipedia.org/wiki/Relative_dating
B.The generator transforms the mechanical energy of the turbine into electrical energy.
C.The generator spins the turbine to create mechanical energy.
D.The generator spins the turbine to create electrical energy.
B. The generator transforms the mechanical energy of the turbine into electrical energy.
Note that a generator uses mechanical energy to turn the wire loop in the magnetic field. This causes electric current to flow, creating electrical energy.