If I solve A and B in a good amount of time. Then if I try to solve C and fail at it once, would I have received higher rating delta if I did not attempt C?

Is this different between all the kinds of rounds? For example, in the latest educational round, it says: //The penalty for each incorrect submission until the submission with a full solution is 10 minutes.

Does this mean that I simply have time deducted? Like if I had 40 minutes remaining, now I only have 30 remaining. And when I submit the correct submission, I am back to 40 minutes. Is that how it works?

How are things different in regular div2 contests?

Sorry, I tried to google but could not find answer and I don't have cp friends (xd).