Answer:
A = bh (the last one)
Step-by-step explanation:
To find the area of a parallelogram, multiply the base by the height. The formula is: A = B * H where B is the base, H is the height, and * means multiply. The base and height of a parallelogram must be perpendicular.
 
        
             
        
        
        
A single drink would cost be $1.55. This is because:
13 + 4x - 6 = 13.20.
(13.20 - 13 + 6) = 6.20.
6.20 / 4 = 1.55
Hope this helped.