The 4 types of air masses are polar, tropical, continental and maritime.
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C. In radiometric dating, scientists place samples of a fossil in certain liquids until the samples dissolve. The rate at which they dissolve indicates the age of the fossil.
 
        
                    
             
        
        
        
Answer: The correct answer is silent mutation . In this type of mutation there is no change in  the phenotype of the individual which means there occurs a mutation where two different amino acid codes for the same protein .There are sequences present in the body where a point mutation occurs but the protein formed is still the same .If you will see the genotype you can easily observe that the amino acid sequence is different but the protein formed is same. Example AAA codes for lysine and the amino acid lysine is formed by AAG .
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<span>Potassium channels open and potassium ions diffuse out of the neuron.</span>
        
             
        
        
        
Answer:
The four stages of the animal life cycle are birth, growth, reproduction and lastly, death. All these animal species go through these stages, however, they manifest differently throughout the animal kingdom.