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: There is at least one z for which z will play squash if and only if z is a lawyer. For all z, z is not a lawyer. For all z, if z were fast, then z is playing squash.
There is at least one z for which if z plays squash, then z is a lawyer can be inferred via the existential biconditional elimination rule. There is at least one z for which if z were a lawyer, then z is playing squash can be inferred via the existential biconditional elimination rule. There is at least one z for which z will not play squash can be inferred via the existential biconditional elimination rule.