The plasma membrane, because it's a selective permeable which means it only allows certain things in like sucrose.
        
             
        
        
        
Answer: 
(y+9)(y-3)
Explanation: 
9*(-3) = -27
9+(-3) = 6
        
             
        
        
        
Oxygen molecules diffuse fast because the main gas in a cell in Carbon Dioxide its like if it was 99.9 percent carbon that .1 percent is oxygen and carbon dioxide being what it is. Automatically overrides the amount of oxygen. Basically it is nonpolar
        
                    
             
        
        
        
Answer: the tails are hydrophobic and the heads are hydrophilic 
 
        
             
        
        
        
Answer: no
Explanation: The solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. This process is called passive transport or facilitated diffusion, and does not require energy.