So the independent variable is the thing that is changed in an experiment and you want to change the amount of rainfall the cactus gets as the hypothesis is about rainfall so the answer would be c). Hope this helps :)
        
                    
             
        
        
        
Answer:
Total 495 liters of natural oil are needed.
Explanation:
It is given that Petrolyn motor oil is a combination of natural oil and synthetic oil. It contains 5 liters of natural oil for every 3 liters of synthetic oil. 
It means the ratio of natural oil and synthetic oil is
 
 
Let in order to make 792 liters of Petrolyn oil he needs x liters of natural oil.
It means the ratio of natural oil and synthetic oil is
 
 
Equate both ratios,

On cross multiplication we get


Divide both sides by 8.


Therefore total 495 liters of natural oil are needed.
 
        
             
        
        
        
C. How long does it take a paper bag to break down?
        
                    
             
        
        
        
Answer:
1: sustainability is an avoidance of the depletion of natural resources in order to maintain an ecological balance.
2: Sustainability means meeting our own needs without compromising the ability of future generations to meet their own needs. 
Explanation:
hope it helps you!
 
        
             
        
        
        
Ground my dude! wanna know how I know! I checked the other answers on the other one :)