Sammy is preparing for a school exam. She orders fried rice from Yummy Asian the night before her exam. The fried rice contains rotten onions, which were put in the fried rice by Bung, one of Yummy Asian's chefs. The next day, Sammy suffers food poisoning, but attempts the exam anyway. She fails the exam and has to repeat the subject over summer.

Is Yummy Asian vicariously liable for Bung's carelessness? Why/why not? Additionally, can Sammy recover the cost of the summer course from Yummy Asian by suing Yummy Asian in the tort of negligence? Why/Why not?

I'm trying to focus on causation and remoteness, as elements of the law of negligence are not relevant.

Thank you