What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all z_2, if z_2 makes tea, then z_2 is a police officer. For all z_2, if z_2 were a police officer, then z_2 is making tea. If Linda plays squash, then Joseph is a police officer.
For all z_2, z_2 will make tea if and only if z_2 is a police officer. For all z_2, z_2 is a police officer if and only if z_2 will make tea.