Answer: The Pulmonary vein blood vessel carries oxygenated blood from the lungs back to the heart. Therefore, it carries the highest concentration of oxygen.
Explanation: i think is the answer not sure hope it help this question :)
 
        
             
        
        
        
One is simple and the other one is compound, simple ;D
        
             
        
        
        
Answer:
Pluto is big enough to be considered a dwarf planet, but it has not been classified as such in some peoples views such as Quaoar and Sedna.
Explanation:
The both reach the otter layers of the solar system just like Pluto and are as I said above big but not big enough to be considered a dwarf planet 
 
        
                    
             
        
        
        
They use their beaks and they push down really hard to stick it