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: Mary is an office clerk or it is not cloudy. Mary is a doctor or it is cloudy. For all x_14, x_14 is an office clerk if and only if x_14 is a doctor.
If it is cloudy, then Mary is an office clerk can be inferred via the rewriting rule. For all x_14, if x_14 were an office clerk, then x_14 is a doctor can be inferred via the universal biconditional elimination rule. For all x_14, if x_14 were a doctor, then x_14 is an office clerk can be inferred via the universal biconditional elimination rule.