The difference between 99 and 99 is: 
The difference between 37 and 33 is: 
The difference between 99 and 99 is: 
The difference between 99 and 91 is: 
The difference between 99 and 99 is: 
The difference between 99 and 49 is: 
The difference between 90 and 91 is: 
The difference between 99 and 99 is: 