Consider the following premises. Michael is not happy. It is cloudy if and only if Michael is happy. If it is not cloudy, then Sarah is making tea. Can we infer the following from them? If we can, name the inference rule being used: Sarah is making tea.
 From the fact that it is cloudy if and only if Michael is happy, and that Michael is not happy we can infer that it is not cloudy via biconditional elimination. Finally, from the fact that if it is not cloudy, then Sarah is making tea, and that it is not cloudy we can infer that Sarah is making tea via modus ponens. Therefore, the answer is yes.