A, S, D, F, G, H, J, K, L, <semi colon ( ; ) and apostrophe ( ' ) as the last two on the right, in front of enter>  
        
             
        
        
        
Answer:to add a column to existing table.
to rename any existing column.
to change datatype of any column or to modify its size.
to drop a column from the table.
Explanation:
hope this help
 
        
             
        
        
        
Answer:
Classless Inter-Domain Routing
Explanation:
Classless Inter-Domain Routing (CIDR), pronounced “cider” or “sidder,” gets its name from the notion that it ignores the traditional A, B, and C class designations for IPv4 addresses and sets the network-host ID boundary wherever it wants to, in a way that simplifies routing across the resulting IP address spaces.
 
        
             
        
        
        
To employ an access key, press and hold down the Alt key as you tap the access key.