What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: If it rains, then Richard is a lawyer. It is raining. Joseph is playing squash.
Richard is a lawyer can be inferred via the modus ponens rule. It is raining and Joseph is playing squash can be inferred via the conjunction rule. Joseph is playing squash and it is raining can be inferred via the conjunction rule.