What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If William were a poet, then it is windy. If it is windy, then William is an astronaut. For all z_3, z_3 is an astronaut if and only if z_3 is a poet.
If William were a poet, then William is an astronaut. For all z_3, if z_3 were an astronaut, then z_3 is a poet. For all z_3, if z_3 were a poet, then z_3 is an astronaut.