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 will make tea if and only if y is an electrician. For all y, if y were an electrician, then y is making tea. For all y, if y makes tea, then y is an electrician.
For all y, y is an electrician if and only if y will make tea can be inferred via the universal biconditional introduction rule. For all y, y will make tea if and only if y is an electrician can be inferred via the universal biconditional introduction rule. For all y, if y makes tea, then y is an electrician can be inferred via the universal biconditional elimination rule. For all y, if y were an electrician, then y is making tea can be inferred via the universal biconditional elimination rule.