The answer is;  15 years
It takes 687 days for mars to orbit the sun once. 8 mars years would, therefore, mean;
8 * 687 = 5496 days
The earth takes 365 days to orbit the sun  once. Therefore, the earth will orbit the following number of times in 8 Mar years;
5496/365 = 15.058
Which is approximately 15 years
 
        
             
        
        
        
Answer:
Since you didnt give an excerpt I can't answer. But I can give you advice. Read through and see If you can find, maybe less food or a higher predator or something like that
Explanation:
 
        
             
        
        
        
The Cell wall is found in plant cells and not animal cells
        
                    
             
        
        
        
Answer:
<em>The correct option is D) oxygen</em>
Explanation:
The splitting of the water molecules during the light-dependent reactions results in the production of 2 electrons, two hydrogen ions and the formation of oxygen gas. The electrons released by this process make ATP by a process which is known as chemiosmosis. The hydrogen ions released during the light-dependent reactions are converted into NADPH during the light-independent reactions. Oxygen is the by-product and is released into the air. The oxygen is used up by other organisms of the earth for cellular respiration. 
 
        
             
        
        
        
The other answers are B C and E