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_6 for which x_6 is not a nurse or x_6 will climb a mountain. For all x_6, if x_6 climbs a mountain, then x_6 is playing tennis. For all x_6, x_6 will go running if and only if x_6 will play tennis. For all x_6, x_6 is a nurse or x_6 will go running.
There is at least one x_6 for which x_6 will go running or x_6 will climb a mountain can be inferred via the existential resolution rule. For all x_6, if x_6 goes running, then x_6 is playing tennis can be inferred via the universal biconditional elimination rule. For all x_6, if x_6 plays tennis, then x_6 is running can be inferred via the universal biconditional elimination rule.