how long
You can't drive to Australia from the UK. It's an island.
2 years
1 week min
2 weeks
40 days approx
About 3 weeks I think
5 to 7 days
About half a dozen.
I think it's about 3 months.
Yes, Since Australia is an island continent, you can visit to Australia from Europe by Sea with Cruises. There are many cruise ships which stop in Australia.
Depends on how fast the ship is traveling.