What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Charles is climbing a mountain if and only if Linda is a writer. If Charles climbs a mountain, then Susan is a police officer. If Charles climbs a mountain, then Susan is a police officer. If Susan were a police officer, then Charles is climbing a mountain. Linda is not a writer.
Charles is climbing a mountain if and only if Susan is a police officer. Charles is climbing a mountain if and only if Susan is a police officer. Susan is a police officer if and only if Charles is climbing a mountain. Susan is a police officer if and only if Charles is climbing a mountain. If Charles climbs a mountain, then Linda is a writer. If Linda were a writer, then Charles is climbing a mountain. Charles is not climbing a mountain.