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 not late. If it is windy, then David is running. It is late if and only if David is running.
If it is late, then David is running can be inferred via the biconditional elimination rule. If David goes running, then it is late can be inferred via the biconditional elimination rule. David is not running can be inferred via the biconditional elimination rule.