What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Barbara is a politician if and only if Thomas is drinking water. If Barbara were a politician, then Elisabeth is a lawyer. If it is sunny, then Thomas is drinking water. If Elisabeth were a lawyer, then it is sunny.
If Barbara were a politician, then it is sunny. If Elisabeth were a lawyer, then Thomas is drinking water. If Barbara were a politician, then Thomas is drinking water. If Thomas drinks water, then Barbara is a politician.