What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? It is cold if and only if James is taking a plane. James is not taking a plane. Patricia is an electrician or Joseph is a mechanic. It is cold if and only if Patricia is an electrician.
If it is cold, then James is taking a plane. If it is cold, then Patricia is an electrician. If James takes a plane, then it is cold. If Patricia were an electrician, then it is cold. It is not cold.