Choice B: 
More photosynthesis leads to more oxygen in the atmosphere and oceans.
        
             
        
        
        
<em>A. 11.0 L is the researcher's volume measurement to the SL units of liter</em>
<u>Explanation:</u>
Given that a researcher recorded that the chemical reaction has water = 2.90 gallon.
We have to convert the researcher's volume into the SL units of liter.
<em>So, we know that 1 gallon = 3.875 liters</em>.
Then we have to convert 2.90 gallons of water in to liters.
Then  , volume in L = =
                                   =  
                                   
= 
<em>Then the required volume in  </em>
</em>
 
        
             
        
        
        
There is only species of a koala but you can ask how many races there are.
The name is, "phascolarctos cinereus".<span />
        
             
        
        
        
In order to study the formation of cancer cells, you should study the life cycle of normal cells as cancer cells are abnormal cells. 
Actually, Normal cells grow, divides and died after an interval of time. And when this process is break down, cancer cells begin to form. They are usually old cells which don't die after their life cycle.
Hope this helps!
        
             
        
        
        
The answer to your question 12