What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If Thomas were a politician, then David is a scientist. If Karen were a bartender, then David is a scientist. It is not snowing. Thomas is a politician or Karen is a bartender. It is snowing if and only if it is cold.
David is a scientist. If it snows, then it is cold. If it is cold, then it is snowing. It is not cold.