Answer:  $500
<u>Step-by-step explanation:</u>
A sells to B at a profit of 10%:    1.10A = B
B sells to C for $577.50 at a profit of 5%:    1.05B = 577.50
Substitute B with 1.10A in the second equation:
1.05(1.10A) = 577.50
        1.155A = 577.50
                A = 500
 
        
             
        
        
        
28 each book 155-15=140 and then 140÷5=28
 
        
             
        
        
        
Answer:
11 cups of dough 
Step-by-step explanation:
1 cup x 11 dumplings = 11 cups of dough needed 
 
        
                    
             
        
        
        
Step-by-step explanation:
you have to put the picture of the polygon or we can't answer the question.
 
        
                    
             
        
        
        
The surface area of the balloon is 249 in².
<h3>What is the surface area of the balloon ?</h3>
A balloon has the shape of a sphere. The distance round the sphere is equal to the circumference of the sphere. 
Circumference of the sphere = 2πr
Where: 
- r = radius 
- π = pi = 22 / 7 
Radius - circumference / 2π
28 / ( 2 x 22/7) = 4.45 inches 
Surface area of a sphere = 4πr²
4 x 22/7 x 4.45² = 249 in²
To learn more about the surface area of a sphere, please check: brainly.com/question/27267844
#SPJ1