What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x, if x sleeps, then x is a nurse. Barbara is a nurse if and only if it is sunny. For all x, if x were a nurse, then x is sleeping. For all x, x will not sleep.
If Barbara were a nurse, then it is sunny. If it is sunny, then Barbara is a nurse. For all x, x is not a nurse. For all x, x will sleep if and only if x is a nurse. For all x, x is a nurse if and only if x will sleep.