Tim Hortons Crew Member interview questions

It was a short but a peaceful interview. I had to only fill up a few questions and then the attender said that I can go to the interview room. The interviewer was kind and nice enough and she was pleasant in her speech and she interviewed me well enough

Tell me about yourself? How are you able to face the problem?What is the toughest decision that you made?what is your salary expectation?How do you deal to a grumpy customer and ended up arguing?