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 a bartender or Jennifer is not a cashier. Jennifer is not a cashier. Jennifer is a cashier if and only if Mary is a bartender.
If Jennifer were a cashier, then Mary is a bartender can be inferred via the rewriting rule. If Jennifer were a cashier, then Mary is a bartender can be inferred via the biconditional elimination rule. If Mary were a bartender, then Jennifer is a cashier can be inferred via the biconditional elimination rule. Mary is not a bartender can be inferred via the biconditional elimination rule.