Step-by-step explanation:
180° = m<A + m<B + m<C
180° = 45° +60° + m<C
180° = 105° + m<C
m<C = 180° - 105 °
m<C = 75°
 
        
             
        
        
        
Answer:
8...the value of d variable =45 degree
corresponding angles are equal(reason)
9. 
 
        
                    
             
        
        
        
Lets say the 3x3 Matrix is 
M =   [1   5   2 ]
         [1   1   7 ]
         [0  -3   7 ]
We apply the Gauss-Jordan elimination method
 (Procedure and result shown in the image below)
 
        
        
        
The answer is 1:11. After it being simplified from 6:66. Hope this helps.
        
                    
             
        
        
        
I'll finish this in a comment or get a mod to open it, but the way it reads, it beeps 67.2 times in those 12 hours. Did you mean per hour?
67.2 / 12 = 5.6    
See comment below. The question is the number of beeps in 1 hour which is 5.6 <<<< Answer