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 x_3, if x_3 were a sailor, then x_3 is making tea. For all x_3, x_3 will not make tea. There is at least one x_3 for which if x_3 works, then x_3 is a sailor. For all x_3, if x_3 makes tea, then x_3 is working.
For all x_3, x_3 is not a sailor can be inferred via the universal modus tollens rule. For all x_3, if x_3 were a sailor, then x_3 is working can be inferred via the universal transitivity rule. There is at least one x_3 for which if x_3 works, then x_3 is making tea can be inferred via the existential transitivity rule. There is at least one x_3 for which if x_3 makes tea, then x_3 is a sailor can be inferred via the existential transitivity rule.