Answer:
The answer is A.
Explanation:
To test if the selenium from the mine has an effect on the fish living in the lake which i assume is close to the mine, testing the tissue of the fish from that lake and comparing it to the selenium levels of the fish from a nearby lake would be a testable hypothesis because there is a comparable aspect and there should be a difference in the numbers between the fish from the two lakes because of their distance to the mine.
I hope this answer helps.
 
        
             
        
        
        
Answer:sponge is one answer.
Explanation:
 
        
             
        
        
        
The epidural anesthesia is a method of pain relief, which is used during the labor pain. It is a well known regional anesthesia. It works by acting as an analgesic, which means a substance that eases the pain, a complete anesthesia or loss of feeling does not occur in the case of epidural anesthesia. It blocks the nerve signals from the lower spinal segments. It is also known as spinal epidural anesthesia or lumbar epidural anesthesia.  
Hence, the black can be filled with lumbar.
 
        
             
        
        
        
Classification systems previously were having very different goals than modern classification systems. If we look at old eras, scientists like Aristotle  and Theophrastus  tried to classify organisms on the basis of apparent characteristics, habitat and simple other traits. 
Old classification systems had alot of errors and flaws. For example they classified fish and whale in one group because they lived in water, now we know fish is amphibian while whale is mammal.
So we can say that the goal o earlier classification system were just to make groups of organisms on the basis of External features.
Goal of modern classification system:
Modern classification approach was started by Linnaeus. It focuses more on biological delimitation and evolutionary histories than mere external characteristics. It organizes organisms in groups in such a way that grouping reflects their evolutionary relatedness. It is not just specie level but also focuses on sub-specie and population level classification.
Thus modern goal is better in many terms and is more reliable than old classification goals.
Hope it helps!
 
        
             
        
        
        
Answer:
carnivores eat meat and herbivorres eat plant 
Explanation: