Are you sure? Yes, I am. -> This anwser should be accepted?
I'd say it's totally ok.
"Are you certain? Yes." wasn't accepted. Although it doesn't include the "I am", isn't it close enough to at least be an alternate answer?
-Are you sure? -I am.
Should that be accepted?
Sounds good, it should be!
I agree, it should!
Didn't accept "are you sure? Yes" which seems like a similar answer. Can't tell if it was the "sure" instead of "certain" part or the "yes"
Ok I tried again with "are you sure - I am" and it was accepted. In many other exercises "yes" was accepted as an answer for this kind of answer