Answer:
Zooplankton help other populations survive by keeping out other herbivores
Explanation:
This is because a keystone species are species that have large effect on the the habitat and through its effect they help to keep the ecosystem in existence. They make sure that the ecosystem exist. They help populations survive by keeping out herbivores and feeding on the algae. They help drive nutrients cycle and transfer energy from algae to invasive fish.
 
        
             
        
        
        
Hi!~
The answer to your question would be <em>micro climate.</em>
<em>Hope this helps!</em>
 
        
             
        
        
        
Answer:
The answer is D. mixed methods. 
Explanation
In Science when you have large data-sets of a Food product then you have to provide its description, Quality and Quality. Here is example for each part as, 
Description:
The scientist have to describe the features of Corn grown in different soils. Corn length could be variable in different soils depending upon the nutrient contents of them. 
Quality:
For any food product quality is most important factor. Scientist have to explain about the quality of Corn grown in different soils because each soil have a different environment of seed growth. 
Quantity:
Finally, the data for the quantity will explain that which soil was more suitable to obtain higher yield of corn.  
 
 
        
                    
             
        
        
        
Answer:
Food - Cow & Rabbit 
Fiber - Alpaca & Camel
Work - Donkey & Horse 
By-products- Cow & Sheep
Research - Monkeys & Rats
Entertainment - Dogs, Cats, Hamsters ect.