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_8, x_8 will read a book if and only if x_8 is an office clerk. For all x_8, x_8 is an office clerk if and only if x_8 will make tea. For all x_8, x_8 will read a book or x_8 will make tea.
For all x_8, if x_8 reads a book, then x_8 is an office clerk can be inferred via the universal biconditional elimination rule. For all x_8, if x_8 were an office clerk, then x_8 is making tea can be inferred via the universal biconditional elimination rule. For all x_8, if x_8 were an office clerk, then x_8 is reading a book can be inferred via the universal biconditional elimination rule. For all x_8, if x_8 makes tea, then x_8 is an office clerk can be inferred via the universal biconditional elimination rule.