I was a little confused myself but if it is asking for the cost of the sneakers after the 20% off from the amount of money the store had to pay, it would be D, $21.84. The way to do this would be to find the cost of the sneakers when the store bought them. You multiply the percentage in decimal form with the cost of the sneakers at the price the store was selling it: 0.3*39 = 11.7. Then, to get the price the store bought them at, you would subtract that price from $39 to get $27.30. Finally, you apply the 20% discount to 27.30 by multiplying 0.2 to it and subtracting that price from 27.30. Then your answer will be $21.84. However, if the problem was asking for the cost of sneakers after the 20% off from the price the store was selling it, it would be A, $31.20. You would have to multiply the 20% discount straight to the price the store is selling the sneakers, $39. Then subtract that price from $39 to get $31.20. 
        
             
        
        
        
Answer:
y= -2x/3+8
Step-by-step explanation:
find 2 points: (0,8) and (6,4)
substitute in y=ax+b
8=0a+b
b=8
4=6a+b
4=6a+8
6a=-4
a=-2/3
 
        
             
        
        
        
Answer:    cubic units.
 cubic units.
Step-by-step explanation:
 You can use this formula for calculate the volume of a cone:
 
 Where "r" is the radius and "h" is the height.
 You know that the diameter of the base of the cone measures 8 units, then, the radius can be found by dividing the diameter by 2:
 
 Since you already know that height and  the radius, you can substitute them into the formula. Then, the volume of this cone is:
 
 
 
        
                    
             
        
        
        
Answer:
 Multiplay 30 by 5 Then multiply five-by-five then Multiply 20 by 5 Then take away your answer