What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all z, z is not a lawyer. For all z, z is a lawyer if and only if z will play tennis. For all z, if z plays tennis, then z is a lawyer.
For all z, z will not play tennis. For all z, if z were a lawyer, then z is playing tennis. For all z, if z plays tennis, then z is a lawyer. For all z, z will not play tennis.