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 y, y is not a police officer. David is sleeping if and only if Jennifer is an office clerk. For all y, y will sleep if and only if y is a police officer.
If David sleeps, then Jennifer is an office clerk can be inferred via the biconditional elimination rule. If Jennifer were an office clerk, then David is sleeping can be inferred via the biconditional elimination rule. For all y, if y sleeps, then y is a police officer can be inferred via the universal biconditional elimination rule. For all y, if y were a police officer, then y is sleeping can be inferred via the universal biconditional elimination rule. For all y, y will not sleep can be inferred via the universal biconditional elimination rule.