Consider the following premises. If Joseph were rich, then Barbara is playing squash. If Barbara plays squash, then it is sunny. For all y_4, y_4 is a bartender if and only if y_4 is rich. It is not sunny. Can we infer the following from them? If we can, name the inference rule being used: If Barbara plays squash, then it is sunny.
That is one of the premises. Therefore, the answer is yes.