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: If John were a scientist, then Susan is sleeping. John is a scientist if and only if James is playing tennis. James is playing tennis or Karen is not playing a game.
If Karen plays a game, then James is playing tennis can be inferred via the rewriting rule. If John were a scientist, then James is playing tennis can be inferred via the biconditional elimination rule. If James plays tennis, then John is a scientist can be inferred via the biconditional elimination rule.