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 Elisabeth were a police officer, then Thomas is sleeping. If James plays squash, then Karen is not a doctor. If it is windy, then Thomas is sleeping. Elisabeth is a police officer or it is windy. Karen is a doctor.
James is not playing squash can be inferred via the modus tollens rule. Thomas is sleeping can be inferred via the disjunction elimination rule.