use library
select avg(noOfCopies) as 'Average no of copies'
from dbo.Available

use library
select max(noOfCopies) as 'Maximum no of copies'
from dbo.Available

use library
select min(noOfCopies) as 'Maximum no of copies'
from dbo.Available

use library
select count(noOfCopies) as 'Maximum no of copies'
from dbo.Available