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: James is taking a plane. James is taking a plane if and only if James is making tea. It is sunny.
James is taking a plane and it is sunny can be inferred via the conjunction rule. It is sunny and James is taking a plane can be inferred via the conjunction rule. If James takes a plane, then James is making tea can be inferred via the biconditional elimination rule. If James makes tea, then James is taking a plane can be inferred via the biconditional elimination rule.