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: There is at least one x_5 for which x_5 is not a police officer. For all x_5, if x_5 makes tea, then x_5 is not writing a letter. For all x_5, x_5 is a police officer or x_5 will write a letter.
There is at least one x_5 for which x_5 will write a letter can be inferred via the existential disjunctive syllogism rule.