What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If Charles climbs a mountain, then Michael is a soldier. For all x_12, x_12 is sad if and only if x_12 will climb a mountain. For all z, z is not a soldier.
For all x_12, if x_12 were sad, then x_12 is climbing a mountain. For all x_12, if x_12 climbs a mountain, then x_12 is sad.