Answer/Explanation:
Recall: 
Volume of a sphere = ⁴/3πr³
Surface Area = 4πr²
✔️For radius (r) = 1 mm:
Volume = ⁴/3 × π × 1³ = 4.19 mm³
Surface Area = 4 × π × 1² = 12.57 mm²
Ratio of volume to surface area = 4.19 : 12.57 = 1:3
✔️For radius (r) = 3 mm:
Volume = ⁴/3 × π × 3³ = 113.1 mm³
Surface Area = 4 × π × 3² = 113.1 mm²
Ratio of volume to surface area = 113.1 : 113.1 = 1:1
 
        
             
        
        
        
A polygenic trait is a trait controlled by many (poly) genes. Human skin color is an example; it thought to be the controlled by about 12 genes. 
       hope it's best answer
        
             
        
        
        
.............Help on what?
 
        
                    
             
        
        
        
<span>microorganisms of different grous are not uniformly susceptible to chemical disinfection due to the level of resistance of the BACTERIA</span>
        
             
        
        
        
The correct answer is option A- HIV virus.
HIV virus is an example of enveloped virus, that has the ability to infect a host cell by attaching itself to it and fusing with the host cell. Once infected, the virus leaves the host cell and moves to another cells to infect them. The HIV virus contains glycoprotein spikes to attach to the host cell.