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: Robert is not cooking. If Mary were not poor, then it is windy. If it is windy, then it is late. Mary is poor if and only if Robert is cooking.
If Mary were not poor, then it is late can be inferred via the transitivity rule. If Mary were poor, then Robert is cooking can be inferred via the biconditional elimination rule. If Robert cooks, then Mary is poor can be inferred via the biconditional elimination rule. Mary is not poor can be inferred via the biconditional elimination rule.