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: There is at least one x for which x will play a game or x will not sleep. For all x, x will play a game if and only if x will sleep.
There is at least one x for which if x sleeps, then x is playing a game can be inferred via the existential rewriting rule. For all x, if x plays a game, then x is sleeping can be inferred via the universal biconditional elimination rule. For all x, if x sleeps, then x is playing a game can be inferred via the universal biconditional elimination rule.