Why do girls sweat when talking to there crush?

Yes, it is extremely normal that when a girl has a crush on a guy and he comes talk to her, the girl will be super nervous. From nerves to faster breathing, along comes the perspiration. How do you feel when you have to take a difficult exam or speak in front of 1000 people? Reactions from nerves are cold hands, hyper perspiration, anxiety etc... When a guy is talking to a girl that suddenly perspires a lot, the guy should be completely understanding as well as making it easy for the girl. With time, the girl won't get nervous anymore.