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: It is cloudy if and only if Jessica is an office clerk. It is overcast if and only if Linda is climbing a mountain. It is not overcast. Linda is climbing a mountain or it is not cloudy.
If it is cloudy, then Linda is climbing a mountain can be inferred via the rewriting rule. If it is cloudy, then Jessica is an office clerk can be inferred via the biconditional elimination rule. If it is overcast, then Linda is climbing a mountain can be inferred via the biconditional elimination rule. If Jessica were an office clerk, then it is cloudy can be inferred via the biconditional elimination rule. If Linda climbs a mountain, then it is overcast can be inferred via the biconditional elimination rule. Linda is not climbing a mountain can be inferred via the biconditional elimination rule.