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_3, if x_3 were a writer, then x_3 is reading a book. For all x_3, x_3 will drink water or x_3 is a writer. There is at least one x_3 for which if x_3 reads a book, then x_3 is a poet. For all x_3, if x_3 drinks water, then x_3 is reading a book.
There is at least one x_3 for which if x_3 were a writer, then x_3 is a poet can be inferred via the existential transitivity rule. There is at least one x_3 for which if x_3 drinks water, then x_3 is a poet can be inferred via the existential transitivity rule. For all x_3, x_3 will read a book can be inferred via the universal disjunction elimination rule.