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: Mary is curious if and only if Linda is sleeping. If Charles were an artist, then Linda is sleeping. Charles is an artist.
Linda is sleeping can be inferred via the modus ponens rule. If Mary were curious, then Linda is sleeping can be inferred via the biconditional elimination rule. If Linda sleeps, then Mary is curious can be inferred via the biconditional elimination rule.