What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_12, x_12 will drive a car if and only if x_12 will make tea. For all x_12, x_12 will drive a car if and only if x_12 is a writer. There is at least one x_12 for which x_12 is not a writer.
For all x_12, if x_12 drives a car, then x_12 is making tea. For all x_12, if x_12 drives a car, then x_12 is a writer. For all x_12, if x_12 makes tea, then x_12 is driving a car. For all x_12, if x_12 were a writer, then x_12 is driving a car. There is at least one x_12 for which x_12 will not drive a car.