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 will play squash. For all z, if z writes a letter, then z is bored. For all z, if z were bored, then z is writing a letter. For all z, if z were bored, then z is not playing squash. For all z, if z were bored, then z is writing a letter.
For all z, z is not bored. For all z, z will write a letter if and only if z is bored. For all z, z will write a letter if and only if z is bored. For all z, z is bored if and only if z will write a letter. For all z, z is bored if and only if z will write a letter.