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: Karen is not playing tennis. For all x_11, x_11 will play tennis if and only if x_11 is a nurse. It is cold.
Karen is not playing tennis and it is cold can be inferred via the conjunction rule. It is cold and Karen is not playing tennis can be inferred via the conjunction rule. For all x_11, if x_11 plays tennis, then x_11 is a nurse can be inferred via the universal biconditional elimination rule. For all x_11, if x_11 were a nurse, then x_11 is playing tennis can be inferred via the universal biconditional elimination rule.