Indeed, the Australian place name Melbourne is spelt correctly.
Yes it is spelled correctly
You have spelled 'still' correctly.
Correctly spelled: mount kosciuskoThis is in Australia, in the Blue mountains about halfway between Sydney and Melbourne. This is the highest point in Australia.
Melbourne is spelled the same in French.
Yes, engineer is spelled correctly in your question.
Flattest is spelled correctly. The others are spelled: silliest, biggest and sweetest.
Yes, surprisingly is spelled with an S. Surprisingly is how you spell it. You spelled it correctly.
You've spelled it correctly.
Convenience (easy access or availability) is correctly spelled.
It should be foreign.
yes, that is correct.
No, "infrachrondal" is not spelled correctly. The correct spelling is "infrachondral."