Consider the following premises. William is not a bartender or Robert is playing a game. Richard is a sailor or William is not a janitor. For all x_16, x_16 is a bartender or x_16 is a janitor. Richard is a sailor if and only if Robert is playing a game. Can we infer the following from them? If we can, name the inference rule being used: Robert is a cashier.
We cannot infer that from the premises. Therefore the answer is no.