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: For all y, y will cook or y is bored. Joseph is not cooking. If it is late, then Barbara is not a sailor. Barbara is a sailor.
It is not late can be inferred via the modus tollens rule. Joseph is not cooking and Barbara is a sailor can be inferred via the conjunction rule. Barbara is a sailor and Joseph is not cooking can be inferred via the conjunction rule.