Star is a brilliantly glowing sphere of hot gas whose energyis produced by an internalnuclear fusion process. Stars are contained in galaxies. A galaxy contains not only stars, but clouds of gas and dust. These clouds are callednebulae, and it is in a nebula where stars are born. In the nebula is hydrogen gas which is pulled together by gravityand starts to spin faster. Over millions of years, more hydrogen gas is pulled into the spinning cloud. The collisions which occur between the hydrogen atoms starts to heat the gas in the cloud. Once the temperature reaches 15,000,000 degrees Celsius, nuclear fusion takes place in the center, or core, of the cloud. The tremendous heat given off by the nuclear fusion process causes the gas to glow creating a protostar. This is the first step in the evolution of a star. The glowing protostar continues to accumulate mass. The amount of mass it can accumulate is determined by the amount ofmatter available in the nebula. Once its mass is stabilized, the star is known as a main sequence star. The new star will continue to glow for millions or even billions of years. As it glows, hydrogen is converted into helium in the core by nuclear fusion. The core starts to become unstable and it starts to contract. The outer shell of the star, which is still mostly hydrogen, starts to expand. As it expands, it cools and starts to glow red. The star has now reached the red giant phase. It is red because it is cooler than the protostar phase and it is a giant because the outer shell has expanded outward. All stars evolve the same way up to the red giant phase. The amount of mass a star has determines which of the following life cycle paths the star will take.
Answer:
The answer is A.
Explanation:
The CR endurance that is given in the question, or cardio respiratory endurance, can be described as the heart's, the muscles' and the lungs' ability to be able to work together effectively through extended periods of physical activity and it can be determined by measuring the amount of oxygen that the body uses in a minute during the said physical activity.
I hope this answer helps.
The fly species Drosophila santomea is found only on a single small island. Thus, this fly is considered to be "Endemic".
Answer:
Some practices from the recommended list of physical/cultural control that you could do year-round to help control pests are as follow:
1. We can use those plant species that are more competitive. These plant species include release of chemical toxins that suppress other plants and insects.
2. Use of large Hight quality seeds.
3. By using narrow spacing in row and increasing seeding rate.
4. By using shallow seeding technique which allow desired plant species to grow and develop faster above the surface of soil.
5. By ensuring that our plant species is perfectly placed in that growing environment which is optimized with every specs.
6. By rotating the crops
7. By rotating plant species with different growing cycles and seasonal cycles.
8. By rotating herbicides with alternative modes of action to delay the herbicide resistance development.
That would be PH and Salinity and Temperature
