It is the second and third boxs
 
        
                    
             
        
        
        
As pair means that 2 socks with the same color need to be drawn for it to be identified as a pair. 
However there is a probability that if u only pick 2 socks, then they could kid each have different COLORS.
By picking 3 socks (bearing in mind there are only 2 types of color) it’s guaranteed that two socks will have the same color.
        
             
        
        
        
Answer: B
Step-by-step explanation: The answer would be B because you would add n the number and 6 then you would multiply it by 2
 
        
             
        
        
        
Since density is the ratio of mass to (in this case) area, we can find the mass of the triangular region  by computing the double integral of the density function over
 by computing the double integral of the density function over  :
:

The boundary of  is determined by a set of lines in the
 is determined by a set of lines in the  plane. One way to describe the region
 plane. One way to describe the region  is by the set of points,
 is by the set of points,

So the mass is



