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: For all x_5, if x_5 works, then x_5 is climbing a mountain. There is at least one x_5 for which if x_5 climbs a mountain, then x_5 is driving a car. For all x_5, if x_5 were a nurse, then x_5 is climbing a mountain. For all x_5, if x_5 were poor, then x_5 is working. For all x_5, x_5 is a nurse or x_5 is poor.
For all x_5, if x_5 were poor, then x_5 is climbing a mountain can be inferred via the universal transitivity rule. There is at least one x_5 for which if x_5 works, then x_5 is driving a car can be inferred via the existential transitivity rule. There is at least one x_5 for which if x_5 were a nurse, then x_5 is driving a car can be inferred via the existential transitivity rule.