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: For all z, z is not an office clerk or z is rich. For all z, z is an office clerk or z will make tea. There is at least one z for which z will work. For all z, z will not make tea.
For all z, z will make tea or z is rich can be inferred via the universal resolution rule.