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 z, z is an office clerk if and only if z is an electrician. There is at least one z for which z is an office clerk if and only if z will sleep.
For all z, if z were an office clerk, then z is an electrician can be inferred via the universal biconditional elimination rule. There is at least one z for which if z were an office clerk, then z is sleeping can be inferred via the existential biconditional elimination rule. For all z, if z were an electrician, then z is an office clerk can be inferred via the universal biconditional elimination rule. There is at least one z for which if z sleeps, then z is an office clerk can be inferred via the existential biconditional elimination rule.