Are the different terminals connected?

The international terminal and domestic terminals are only connected via tram. The domestic terminals are connected by trams and walkways.

The terminals are not directly connected. But you can get between Terminals 1 & 3 by taking the trams from either terminal and connecting through the D gates concourse. You can only do this after clearing security checkpoints.

Yes

Yes, kinda

Yes, they are connected by trains

No you have to take the train

They're connected, but there are separate security gates for A, B+C, and D+E