"Yes, bribing the police is a crime in Australia. Both offering a bribe to a police officer and accepting a bribe as a police officer are serious offenses."
Australian Citizenship Test gives you access to many more tests than just the one practice test available on the government website. That official sample test is good for giving you an idea of what to expect on the real test. But it can't help you prepare fully. Nor does reading the Australian Citizenship: Our Bond material alone.