Answer:Warming of the Earth's climate and associated changes to oceans were the most likely causes of the extinctions. At the end of the Permian Period volcanic activity on a massive scale in what is now Siberia led to a huge outpouring of lava.
Explanation:
 
        
             
        
        
        
Answer:
D
Explanation:
Absolute age is defined as the numeric age of fossils.
To identify the absolute age of a fossil,  the amount of certain radioactive elements in the rock are measured. When fossils are formed in the rocks, a small amounts of radioactive elements is included in it. The process to identify age of fossil using radioactive elements is known radiometric dating. So, radioactive isotope and its decay product gives absolute age of fossils.
Hence, the correct answer is "D".
 
        
             
        
        
        
The ribosome is involved with the bonding of amino acids
        
             
        
        
        
I would say true. I say this because there have been times where scientists find out that there are better ways of performing experiments, or found that certain materials work better for certain tasks. (Especially true in medicinal fields!)