What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If it is cold, then Michael is a sailor. Michael is not a sailor. For all y, y will write a letter if and only if y will climb a mountain. Jessica is not climbing a mountain.
It is not cold. Michael is not a sailor and Jessica is not climbing a mountain. Jessica is not climbing a mountain and Michael is not a sailor. For all y, if y writes a letter, then y is climbing a mountain. For all y, if y climbs a mountain, then y is writing a letter.