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_12 for which x_12 will make tea and x_12 is a lawyer. For all x_12, if x_12 were a scientist, then x_12 is an astronaut. For all x_12, if x_12 climbs a mountain, then x_12 is an astronaut. For all x_12, x_12 will climb a mountain.
For all x_12, x_12 is an astronaut can be inferred via the universal modus ponens rule. There is at least one x_12 for which x_12 will make tea can be inferred via the existential simplification rule. There is at least one x_12 for which x_12 is a lawyer can be inferred via the existential simplification rule.