What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: It is cold if and only if it is sunny. If it is sunny, then it is cold.
If it is cold, then it is sunny can be inferred via the biconditional elimination rule. If it is sunny, then it is cold can be inferred via the biconditional elimination rule.