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_9, x_9 will not read a book. There is at least one x_9 for which if x_9 were a writer, then x_9 is making tea. For all x_9, x_9 will read a book if and only if x_9 will make tea.
For all x_9, if x_9 reads a book, then x_9 is making tea can be inferred via the universal biconditional elimination rule. For all x_9, if x_9 makes tea, then x_9 is reading a book can be inferred via the universal biconditional elimination rule. For all x_9, x_9 will not make tea can be inferred via the universal biconditional elimination rule.