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 x_11, if x_11 plays squash, then x_11 is reading a book. There is at least one x_11 for which x_11 will play squash or x_11 will cook. For all x_11, if x_11 cooks, then x_11 is reading a book. For all x_11, x_11 will drink water.
There is at least one x_11 for which x_11 will read a book can be inferred via the existential disjunction elimination rule.