Consider the following premises. It is not cold if and only if it is late. It is cold if and only if Susan is an office clerk. Susan is not an office clerk. Can we infer the following from them? If we can, name the inference rule being used: It is late.
 From the fact that it is cold if and only if Susan is an office clerk, and that Susan is not an office clerk we can infer that it is not cold via biconditional elimination. From the fact that it is not cold if and only if it is late we can infer that if it is not cold, then it is late via biconditional elimination. Finally, from the fact that if it is not cold, then it is late, and that it is not cold we can infer that it is late via modus ponens. Therefore, the answer is yes.