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: Joseph is reading a book. If Thomas works, then Charles is making tea. David is playing tennis or Thomas is working. If David plays tennis, then Charles is making tea. For all x_14, if x_14 reads a book, then x_14 is running.
Charles is making tea can be inferred via the disjunction elimination rule. There is at least one x for which x will read a book can be inferred via the existential generalization rule.