What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_14, x_14 will make tea if and only if x_14 will listen to a song. Barbara is listening to a song if and only if Barbara is making tea.
If Barbara listens to a song, then Barbara is making tea. If Barbara makes tea, then Barbara is listening to a song. For all x_14, if x_14 makes tea, then x_14 is listening to a song. For all x_14, if x_14 listens to a song, then x_14 is making tea.