A. Warm air rises and F. Cooler air travels back to the ocean surface
I believe it is the introduction which should be relatively brief. You shouldn't prolong it too much, because the emphasis should be put on the main part of your speech, and not so much on the introduction.
I would love to help answer this but there isn’t enough information to do so!
Okay first of all, what topic did you choose?
Second, can you choose any topic ?
Thrid, there's no thrid....
Answer:
The distinction between murder and hunting.