1. Both are correct. 2. Yes, they are.^^/ "-고말고(요)" is used to confirm what somebody has said or strongly agree with somebody's opinion while "-고 말고(with space between 고 and 말고)" can be used to mean "whether...or not", and often used in a situation where somebody needs to make a decision. e.g. A : 그 사람은 오나요? (Is he coming?) B : 물론이죠, 오고말고요.(definitely, he's coming) As for "-고 말고" 오고 말고는 너한테 달려있다 = It's up to you whether you come or not. \^o^/