⟩ What kind of salary are you looking for a sales assistant?
This is a very difficult question to answer, because with this question, the interviewer wants to know the value of your effort for yourself. A sample of bad question might be "Any salary is fine for me", this shows that you do not value your effort.
A sample of good question might be:
In my last job my salary was $6000, but I think that you will see that I worth more.