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 y, if y drinks water, then y is listening to a song. For all y, if y listens to a song, then y is drinking water. For all y, if y drinks water, then y is making tea. There is at least one y for which if y makes tea, then y is listening to a song.
For all y, if y listens to a song, then y is making tea can be inferred via the universal transitivity rule. There is at least one y for which if y makes tea, then y is drinking water can be inferred via the existential transitivity rule. There is at least one y for which if y drinks water, then y is listening to a song can be inferred via the existential transitivity rule. For all y, y will drink water if and only if y will listen to a song can be inferred via the universal biconditional introduction rule. For all y, y will listen to a song if and only if y will drink water can be inferred via the universal biconditional introduction rule.