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: For all x_13, x_13 will listen to a song or x_13 is a nurse. Thomas is listening to a song if and only if Linda is a carpenter. Thomas is a nurse if and only if Linda is a carpenter.
If Thomas listens to a song, then Linda is a carpenter can be inferred via the biconditional elimination rule. If Thomas were a nurse, then Linda is a carpenter can be inferred via the biconditional elimination rule. If Linda were a carpenter, then Thomas is listening to a song can be inferred via the biconditional elimination rule. If Linda were a carpenter, then Thomas is a nurse can be inferred via the biconditional elimination rule.