It depends greatly on the person. Some people can fake their emotions very effectively, including their tone of voice. The majority of people however, do let some of their emotions show through. You can also watch body language, and their eyes, which are usually a dead give away.

Yes. But I don't care.

Most of the time. :)

Yes of course.

Yes.

Sure. If I suspect they are, I will ask them if there is anything we need to talk about.

It may not be a problem with you, it might be that they are having a difficult day and is losing grips on their emotions causing their attitude. However, if they were rude to me I would not hesitate to ask if I offended them in some way or another.

Appearance and tone provide the first impression. But we know that first impressions are not always the best impressions. "In as little as 8 to 30 seconds, people form fairly lasting impressions about you -- impressions about your intelligence, success, confidence, competence, physical fitness, professionalism, etc. The axiom "you never get a second chance to make a first impression" is so true. And it's compounded by the fact that people generally do not change their minds about someone once they've formed that impression." http://www.bizjournals.com/charlotte/stories/1998/03/09/smallb3.html "Our two minds .... One is an act of the emotional mind, the other of the rational mind. In a very real sense we have two minds, one that thinks and one that feels" (Daniel Goleman, Emotional Intelligence, Bloomsbury Publishing, London, 1996, page 8). This rational mind is also called the faculty of logic and reason. This rational mind is also called the faculty of logic and reason. The emotional mind provides the first impression. After some acquaintance with a person, the rational mind provides a more logical impression of that person.

I definately can tell by the tone in someones voice and by the body expressions.