Erica paid for goods she bought at the electronic checkout by the exit

turnstile of the supermarket. Just after she paid for the goods, Cam, the

floor supervisor, took over the exit and, mistakenly believing that Erica had

not paid, refused to allow her to leave with the groceries unless she paid for

them again. Erica refused, so Cam asked her to accompany him to the

office to discuss the matter further. When Erica refused, Cam took her by

the arm and started to pull her towards the office. Erica responded by first

telling Cam to stop, and then when he didn't she hit him in the face with her

grocery bag, knocking him unconscious. Discuss.

Briefly explain the difference between public and private nuisance