It is because that's a place where no one lives so they're safe.
        
             
        
        
        
those are nucleotides 
since all three of them contain deoxyribose (because there's only one hydroxil group) they are DNA nucleotides
the first nucleotide has cytosine as it's nitrogenous base 
the second nucleotide has adenine as it's nitrogenous base 
the third nucleotide has thymine as it's nitrogenous base
 
        
             
        
        
        
Answer:
Phenotype 
Genotype
Explanation:
Phenotype is the physical appearance because it's the outward expression of the person, which is determined by one's Genotype.
 
        
             
        
        
        
<span>The area was most likely eroded by a earthquake. Feel free to message me if you have any other questions.
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1. Explain why the distribution of fossils in Figure 1 supports the hypothesis that the extinction of these species was the result of a sudden environmental change.
This hypothesis can be supported because all the fossils accumulate almost at the same age of the rock layer. That is, all the fossils died almost at the same time.
2. Describe an environmental change that could have produced this type of fossil distribution.
Good examples of sudden environmental changes are volcanoes. When a rash occurs, the whole environment suddenly changes for different reasons such as ash or lava, and all living things can die immediately or in a few years by the change in the ecosystem.
3. Explain why the distribution of fossils in Figure 2 supports the hypothesis that the extinction of these species was the result of a gradual environmental change.
This is because the fossils accumulate at different ages of the rock layer, that means, the species dying over time. The gradual descent of the fossils is observed.
4. Describe an environmental change that could produce this type of fossil distribution.
For example, if a climate change occurs - the temperature increases or decreases - it can cause the trees or plants to die and all the animals in the ecosystem also die when they have no food. But this process is sequential, so the change can take years, centuries or even millions of years.
I hope this can help you.