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_7 for which x_7 will drive a car if and only if x_7 is a writer. For all x_7, x_7 will not read a book or x_7 will drink water. For all x_7, x_7 will read a book or x_7 is a writer. For all x_7, if x_7 drinks water, then x_7 is driving a car.
For all x_7, x_7 is a writer or x_7 will drink water can be inferred via the universal resolution rule. There is at least one x_7 for which if x_7 drives a car, then x_7 is a writer can be inferred via the existential biconditional elimination rule. There is at least one x_7 for which if x_7 were a writer, then x_7 is driving a car can be inferred via the existential biconditional elimination rule.