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: If it is sunny, then Thomas is a taxi driver. If Thomas were a taxi driver, then it is snowing. It is not snowing. If it is cloudy, then it is sunny.
Thomas is not a taxi driver can be inferred via the modus tollens rule. If it is sunny, then it is snowing can be inferred via the transitivity rule. If it is cloudy, then Thomas is a taxi driver can be inferred via the transitivity rule.