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: If Patricia were sad, then Patricia is drinking water. It is overcast if and only if Patricia is sad. It is overcast if and only if Patricia is drinking water.
If it is overcast, then Patricia is sad can be inferred via the biconditional elimination rule. If it is overcast, then Patricia is drinking water can be inferred via the biconditional elimination rule. If Patricia were sad, then it is overcast can be inferred via the biconditional elimination rule. If Patricia drinks water, then it is overcast can be inferred via the biconditional elimination rule.