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: forall x_4: ~S(x_4). S(b) <-> p. p <-> t.
S(b) -> p can be inferred via the biconditional elimination rule. p -> t can be inferred via the biconditional elimination rule. p -> S(b) can be inferred via the biconditional elimination rule. t -> p can be inferred via the biconditional elimination rule.