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: David is playing a game if and only if Elisabeth is working. If it is windy, then Elisabeth is working. If David plays a game, then it is windy.
If David plays a game, then Elisabeth is working can be inferred via the transitivity rule. If David plays a game, then Elisabeth is working can be inferred via the biconditional elimination rule. If Elisabeth works, then David is playing a game can be inferred via the biconditional elimination rule.