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_12, if x_12 were bored, then x_12 is a taxi driver. For all x_12, x_12 will not work. There is at least one x_12 for which x_12 is a soldier if and only if x_12 is bored. For all x_12, x_12 will work if and only if x_12 is a soldier. For all x_12, if x_12 were a taxi driver, then x_12 is bored.
For all x_12, x_12 is bored if and only if x_12 is a taxi driver can be inferred via the universal biconditional introduction rule. For all x_12, x_12 is a taxi driver if and only if x_12 is bored can be inferred via the universal biconditional introduction rule. For all x_12, if x_12 works, then x_12 is a soldier can be inferred via the universal biconditional elimination rule. There is at least one x_12 for which if x_12 were a soldier, then x_12 is bored can be inferred via the existential biconditional elimination rule. For all x_12, if x_12 were a soldier, then x_12 is working can be inferred via the universal biconditional elimination rule. There is at least one x_12 for which if x_12 were bored, then x_12 is a soldier can be inferred via the existential biconditional elimination rule. For all x_12, x_12 is not a soldier can be inferred via the universal biconditional elimination rule.