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: Charles is a lawyer if and only if Michael is playing a game. It is not overcast. Charles is a lawyer if and only if it is overcast. If Michael doesn't play a game, then Joseph is working.
If Charles were a lawyer, then Michael is playing a game can be inferred via the biconditional elimination rule. If Charles were a lawyer, then it is overcast can be inferred via the biconditional elimination rule. If Michael plays a game, then Charles is a lawyer can be inferred via the biconditional elimination rule. If it is overcast, then Charles is a lawyer can be inferred via the biconditional elimination rule. Charles is not a lawyer can be inferred via the biconditional elimination rule.