The third one :) I hope I did it right
        
                    
             
        
        
        
Answer:
r = 9
Step-by-step explanation:
cross multiply 
9 * r = 81
9r = 81
divide both sides by 9
r= 81/9 
r = 9
 
        
             
        
        
        
Answer:
the answer is b 1/4 its means got it 1 time same after throwing it 4 times
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer: x = -14/5
Step-by-step explanation: We shall begin by expanding the brackets for both sides of the equation
-2/3 (x + 2) = 1/6 (x + 6)
(-2x/3) -4/3 = (x/6) + 1
By collecting like terms we now have
(-2x/3) - (x/6) = 1 + 4/3
(-4x - x)/6 = 7/3
-5x/6 = 7/3
By cross multiplication we now have
-5x (3) = 7 (6)
-15x = 42
x = -(42/15) {simplify further by dividing the RHS by 3}
x = -14/5
Therefore x equals, minus fourteen over five (-14/5)
 
        
             
        
        
        
Answer:
we have: 

=> r²h = 10.18 = 9.20 = 5.36 = 6.30 = 4.45 = 12.15
=> only r²h = 5.36 satisfy the problem
=> h = 5
h = 5 r = 6
h = 5 r = 6=> d = 12