Answer to Question 1
Growling, when it is being aggressive, screaming in pain or fear.
Answer to Question 2
Many of the laws regarding ferrets were enacted before there was an understanding of their behaviors. The concerns were often based on hearsay: that ferrets would attack and kill human infants, that they would decimate other animal populations, and that they were carriers of rabies. These concerns have now been largely discounted through public education, and many areas have repealed laws that prohibited keeping ferrets as pets.