What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If James were a mechanic, then James is making tea. Richard is sleeping if and only if James is a mechanic. If Robert listens to a song, then Richard is sleeping. James is not making tea.
James is not a mechanic. If Richard sleeps, then James is a mechanic. If James were a mechanic, then Richard is sleeping.