Answer:
Option B, Barr graph
Explanation:
A bar graph is used for comparing several items all together based on any certain parameter.  
Here, the lead content is the comparison parameter while the six sample of contaminated water wells acts as different items being compared.  
A line graph is good to show a continous varying data set, while a circle graph is good to represent the component constitution of any major substance and a data table is best to represent a data set with multiple attributes.
Hence, option B is correct
 
        
             
        
        
        
Predators possess usually good senses to find their prey and special abilities to trap the prey. Predatory birds, for example, had an outstanding eyesight and sometimes hearing, for the case of the owls while other predators, like many species of mammals, have a very high sense of smell that helps them locate prey. Many predators are very fast, and use their speed to help capture their prey, some are fastest runners, fast fliers and fast swimmers. 
        
                    
             
        
        
        
Answer:
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the most essential part for biological inheritance.
Explanation:
I hope it's help u :)
 
        
             
        
        
        
Protein elastin is used to made elastic fiber, component of connective tissue that found abundant in blood vessels, bones, tendon and skin. The effect should be prominent in those organs. 
Aorta is the biggest artery blood vessels and it need more elasticity to withstand the pressure of the ventricle. Less elasticity makes aorta become enlarged. The bone will lose density and become thinner. The tendon in heart valve will be weaken and might cause the heart valve disease. The skin will lose elasticity, so it will be easier to stretch.