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: Thomas is not listening to a song. Thomas is listening to a song if and only if Richard is an office clerk. Richard is an office clerk if and only if Joseph is reading a book.
If Thomas listens to a song, then Richard is an office clerk can be inferred via the biconditional elimination rule. If Richard were an office clerk, then Joseph is reading a book can be inferred via the biconditional elimination rule. If Richard were an office clerk, then Thomas is listening to a song can be inferred via the biconditional elimination rule. If Joseph reads a book, then Richard is an office clerk can be inferred via the biconditional elimination rule. Richard is not an office clerk can be inferred via the biconditional elimination rule.