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: Elisabeth is sad if and only if Jessica is rich. If it is windy, then Elisabeth is sad. Elisabeth is not sad. If Jessica were rich, then it is windy.
It is not windy can be inferred via the modus tollens rule. If Jessica were rich, then Elisabeth is sad can be inferred via the transitivity rule. If Elisabeth were sad, then Jessica is rich can be inferred via the biconditional elimination rule. If Jessica were rich, then Elisabeth is sad can be inferred via the biconditional elimination rule. Jessica is not rich can be inferred via the biconditional elimination rule.