Consider the following premises. For all y, y is a cashier if and only if y is an artist. For all y, if y were fast, then y is an electrician. There is at least one y for which if y were an electrician, then y is an artist. Can we infer the following from them? If we can, name the inference rule being used: For all y, y is a cashier if and only if y is an artist.
That is one of the premises. Therefore, the answer is yes.