Answer:
Question 1
D
Question 2
C
Question 3
D
Explanation:
1. An ecosystem is MOST likely to return to its original condition after Tall prairie grass burns after being struck by lightning.
Here is a research paper in which they explained how this happened. (Komarek, E. V. (1971). Lightning and fire ecology in Africa. In Tall Timbers Fire Ecology Conference (Vol. 11, pp. 473-509).)
2. In some national parks, controlled fires are maintained by firefighters. The major reasons for using controlled burns to maintain certain ecosystems is to give nonnative plants a chance to colonize the region.
A recent article provided the insight of this situation (Xanthopoulos, G., Delogu, G. M., Leone, V., Correia, F. J., & Magalhães, C. G. (2020). Firefighting approaches and extreme wildfires. In Extreme Wildfire Events and Disasters (pp. 117-132). Elsevier.)
3. One reason for the change in the Galápagos ecosystem has been the introduction of species that were not on the island before, such as donkeys, goats, cats, dogs, and insects. The introduction of nonnative species MOST likely disrupt the balance of life on the islands due to greater competition for limited food sources.
Scientist said that food competition is actually a struggle to survive in any ecosystem here is the reference paper (Eckhardt, R. C. (1972). Introduced plants and animals in the Galapagos Islands. Bioscience, 22(10), 585-590.)
Answer : Option D) Fewer people have skin pigmentation lighter than the central peak than people who have pigmentation darker than the central peak.
Explanation : The quantitative variation which is shown for the skin is best explained by option D. Which shows that fewer people have got skin pigmentation which is lighter than the central peak in the graph, compared to the people who have darker pigmentation than the central peak.
Answer: Mixture
Explanation:
If there is and unstable element composition of say, pure graphite an un-pure gold then a chemical reaction will most likely be used to separate the two elements.
prevents backflow into the left atrium