I do my homework on Friday if I can, I like to have my weekends free to do whatever I want :)
 
        
                    
             
        
        
        
Keeping track of common files by using a lot of computers and mobiles all through the day may be hard. A good example is when you synchronized your mobile and computer devices. If you check an email using your computer, it will also appear in your smartphone. This will be a lot easier to track your email through both of your devices than having not to be synced at all.
        
             
        
        
        
Do you mean like a phone 
IPhones 
Samsung 
Moto z
Lge sorry if this isn't what you asked
        
                    
             
        
        
        
 
A=Application software
C=Microcomputer
D=hybrid computers
E=digital computer
F=Handheld computer
G=Dextop computer
 
Sorry,i couldn't help you in B.
 
        
                    
             
        
        
        
Answer:
For question a, it simplifies.  If you re-express it in boolean algebra, you get:
(a + b) + (!a + b)
= a + !a + b
= b
So you can simplify that circuit to just:
x = 1 if b = 1
(edit: or rather, x = b)
For question b, let's try it:
(!a!b)(!b + c)
= !a!b + !a!bc
= !a!b(1 + c)
= !a!b
So that one can be simplified to 
a = 0 and b = 0
I have no good means of drawing them here, but hopefully the simplification helped!