(a) That's right. The Commonwealth of Australia consists of six states and ten other 'territories', two of which are 'mainland' territories and the rest of which are 'external'. They are:

- Northern Territory (mainland)

- Australian Capital Territory (mainland)

- Australian Antarctic Territory

- Ashmore & Cartier Islands

- Christmas Island

- Cocos (Keeling) Islands

- Coral Sea Islands

- Jervis Bay Territory

- Heard Island and McDonald Island

- Norfolk Island