Bob is a lackadaisical teenager. In conversation, his responses are very limited.
Bob answers 'Sure.' if you ask him a question, such as "How are you?".
He answers 'Whoa, chill out!' if you YELL AT HIM (in all capitals).
He answers 'Calm down, I know what I'm doing!' if you yell a question at him.
He says 'Fine. Be that way!' if you address him without actually saying 
anything.
He answers 'Whatever.' to anything else.
Bob's conversational partner is a purist when it comes to written communication and always follows normal rules regarding sentence punctuation in English.