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: There is at least one x_8 for which x_8 will take a plane if and only if x_8 will listen to a song. For all x_8, x_8 will read a book if and only if x_8 will work. For all x_8, x_8 will not work. For all x_8, if x_8 listens to a song, then x_8 is reading a book.
For all x_8, if x_8 reads a book, then x_8 is working can be inferred via the universal biconditional elimination rule. There is at least one x_8 for which if x_8 takes a plane, then x_8 is listening to a song can be inferred via the existential biconditional elimination rule. For all x_8, if x_8 works, then x_8 is reading a book can be inferred via the universal biconditional elimination rule. There is at least one x_8 for which if x_8 listens to a song, then x_8 is taking a plane can be inferred via the existential biconditional elimination rule. For all x_8, x_8 will not read a book can be inferred via the universal biconditional elimination rule.