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_12, x_12 is not a scientist. There is at least one x_12 for which x_12 will drink water or x_12 will cook. For all x_12, if x_12 cooks, then x_12 is a scientist. For all x_12, if x_12 drinks water, then x_12 is a scientist.
For all x_12, x_12 will not cook can be inferred via the universal modus tollens rule. For all x_12, x_12 will not drink water can be inferred via the universal modus tollens rule. There is at least one x_12 for which x_12 is a scientist can be inferred via the existential disjunction elimination rule.