What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one x_13 for which x_13 will drive a car if and only if x_13 is a taxi driver. For all x_13, x_13 will drive a car or x_13 is excited. For all x_13, if x_13 were excited, then x_13 is a taxi driver.
There is at least one x_13 for which if x_13 drives a car, then x_13 is a taxi driver. There is at least one x_13 for which if x_13 were a taxi driver, then x_13 is driving a car.