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: Jessica is an office clerk if and only if William is a soldier. If Karen makes tea, then Jessica is an office clerk. If Jessica were an office clerk, then Karen is making tea.
Karen is making tea if and only if Jessica is an office clerk can be inferred via the biconditional introduction rule. Jessica is an office clerk if and only if Karen is making tea can be inferred via the biconditional introduction rule. If Jessica were an office clerk, then William is a soldier can be inferred via the biconditional elimination rule. If William were a soldier, then Jessica is an office clerk can be inferred via the biconditional elimination rule.