What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Sarah is an electrician. If Sarah were an electrician, then Sarah is an office clerk. Barbara is climbing a mountain if and only if Sarah is an office clerk. Barbara is climbing a mountain if and only if Michael is a nurse.
Sarah is an office clerk. If Barbara climbs a mountain, then Sarah is an office clerk. If Barbara climbs a mountain, then Michael is a nurse. If Sarah were an office clerk, then Barbara is climbing a mountain. If Michael were a nurse, then Barbara is climbing a mountain.