How to access a table from one database to another database

Hai all,
I have 2 databases namee PAO and CAS.
PAO contains 3 schemas named Public,pao,sts
CAS contains 4 schemas named Public,cao,sts,reports

Now i am in PAO database..now i want access table 'activity' in schema
'cas' in CAS database.
How it is posible.

2nd thing is...

i have 2 servers access i.e local and mainserver.

How access table from one server to another server?

please tel me...because we need this one

Thanks and regards

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Vivekananda.R <mailto:vivekanandaswamyr(at)infics(dot)com> | Software Engineer
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