Q.
                  Figure shows a combination of logic gates.
To what single gate is this combination equivalent?
                Solution:

 
 
  
  
  
   
  
  
  
 0  
 0  
 1  
 1  
0  
   
  
 0  
 1  
 1  
 0  
1  
   
  
 1  
 0  
 0  
 1  
1  
   
  
 1  
 1  
 0  
 0  
0  
   
 
  
 
 
 
The combination of logic gates can be replaced by a single EX-OR gate.
                | 0 | 0 | 1 | 1 | 0 | 
| 0 | 1 | 1 | 0 | 1 | 
| 1 | 0 | 0 | 1 | 1 | 
| 1 | 1 | 0 | 0 | 0 |