What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Thomas is taking a plane if and only if Linda is running. Thomas is taking a plane if and only if Linda is running.
If Thomas takes a plane, then Linda is running. If Thomas takes a plane, then Linda is running. If Linda goes running, then Thomas is taking a plane. If Linda goes running, then Thomas is taking a plane.