What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x, x will drive a car if and only if x will go running. For all x, x is a sailor if and only if x is a taxi driver. For all x, x is a taxi driver if and only if x will drive a car. For all x, x is not a sailor.
For all x, if x drives a car, then x is running. For all x, if x were a sailor, then x is a taxi driver. For all x, if x were a taxi driver, then x is driving a car. For all x, if x goes running, then x is driving a car. For all x, if x were a taxi driver, then x is a sailor. For all x, if x drives a car, then x is a taxi driver. For all x, x is not a taxi driver.