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 z_3, z_3 is a musician or z_3 will play tennis. There is at least one z_3 for which if z_3 were a musician, then z_3 is poor. For all z_3, if z_3 were poor, then z_3 is curious. For all z_3, if z_3 plays tennis, then z_3 is poor.
For all z_3, if z_3 plays tennis, then z_3 is curious can be inferred via the universal transitivity rule. There is at least one z_3 for which if z_3 were a musician, then z_3 is curious can be inferred via the existential transitivity rule. There is at least one z_3 for which z_3 is poor can be inferred via the existential disjunction elimination rule.