Answer: 3.75 g
Step-by-step explanation:
Assume the weight of the square is x. 
The hanger is in balance so the left side is equal to the right side. 
Equation therefore is:
Triangle + Square + 3 * circle = 5* square + circle
3 + x + (3 * 6) = 5x + 6
3 + x + 18 = 5x + 6
5x - x = 3 + 18 - 6
4x = 15
x = 15/4
x =  3.75 g
 
        
             
        
        
        
Given two points (x₁,y₁) and (x₂,y₂) the midpoint would be:
M=((x₁+x₂)/2 , (y₁+y₂)/2)
In this case, the points would be: (-8,-7) and (-7,-8); therefore:
M=((-8-7)/2 , (-7-8)/2)=(-15/2,-15/2)
Answer: C.)  (-15/2 , -15,2)
        
             
        
        
        
Answer:
C)  2
Step-by-step explanation:
step 1:  Find mean of data set
2+4+4+5+7+8 = 30
30/6 = 5
Mean = 5
step 2: subtract each data value from the mean and square it
5-2 = 3;   3² = 9
5-4 = 1;   1² = 1
5-4 = 1;   1² = 1 
5-5 = 0;   0² = 0
5-7 = -2;   (-2²) = 4
5-8 = -3;   (-3²) = 9
Add the squared results:
9+1+1+0+4+9 = 24
Divide 24 by 6 to get the Variance of 4
Take the square root of the Variance to get the Standard Deviation
 = 2
 = 2