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_12, x_12 will climb a mountain and x_12 will cook. There is at least one x_12 for which x_12 will listen to a song and x_12 will read a book.
For all x_12, x_12 will climb a mountain can be inferred via the universal simplification rule. For all x_12, x_12 will cook can be inferred via the universal simplification rule. There is at least one x_12 for which x_12 will listen to a song can be inferred via the existential simplification rule. There is at least one x_12 for which x_12 will read a book can be inferred via the existential simplification rule.