I believe that answer is B. (The second one)
Hope this helped !!
        
             
        
        
        
We just need to get the perimeter of the backyard.
Whole rectangle: length = 7ft ; width = 5 ft
Perimeter = 2(7+5) = 2(12) = 24 ft
        
             
        
        
        
Answer: 7/12 of the beads are blue and green
Step-by-step explanation: To make both denominators of fraction 3/12 and 1/3 equal, you have to change both denominators to the lowest common denominator. Since the LCD (lowest common denominator) is 12 you have to multiply 1/3 by 4 to make the two denominators match. 
1/3 x 4/4= 4/12
Then to find the total fraction of both green and blue beads on the necklace, you simply have to add the two fractions together.
4/12+3/12= 7/12
hope this helps :)
 
        
             
        
        
        
Do pemdas and once you got your answer from that keep checking