1. No, this includes land, air, and sea units placed in any adjacent seazones.
2. No, territories can only be claimed by land units.
3. It has to be in an IC.
4. Only for anti-aircraft. Submarines opening fire is for their attack value (2 or 3 with super subs technology), and the battleships bombardment hits on a 4.
5. Yes, the bomber can land in brazil, as it is friendly territory. The 3 IPCs from Brazil are already included in the USA’s production, so theres no need to add them in.
Once again, only land units can capture territory.