The correct answer is - a front.
On this image, the lines are representing a front, and since the signs are marked with blue color, it means that it is a cold front. The fronts are advancing masses of air. In this case, we have a cold front, thus we have advancing cold air masses in the western part of the US, and in the Great Lakes region and the northeastern part of the country. This means that these areas will be affected by colder air masses, that will bring in higher air pressure, colder weather, and cold winds from the direction from which these cold fronts are coming.
 
        
                    
             
        
        
        
Answer:
keratin, collagen, and elastin are some
Explanation:
 
        
             
        
        
        
https://volcano.si.edu/faq/index.cfm?question=eruptionsbyyear&checkyear=2019
Click that link and It will come up with 50+ volcanic eruptions and will tell you all about them
 
        
             
        
        
        
Answer: It is basically when DNA is added to a gene to enhance the way a person performs in athletics.
Explanation:
 
        
             
        
        
        
True ............. its speeds up the rate of reaction