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_8, if x_8 drives a car, then x_8 is a carpenter. For all x_8, if x_8 were a carpenter, then x_8 is a taxi driver. For all x_8, if x_8 were a taxi driver, then x_8 is a carpenter. There is at least one x_8 for which x_8 is not poor or x_8 will drive a car. For all x_8, x_8 is poor or x_8 is a taxi driver.
For all x_8, if x_8 drives a car, then x_8 is a taxi driver can be inferred via the universal transitivity rule. There is at least one x_8 for which x_8 is a taxi driver or x_8 will drive a car can be inferred via the existential resolution rule. For all x_8, x_8 is a carpenter if and only if x_8 is a taxi driver can be inferred via the universal biconditional introduction rule. For all x_8, x_8 is a taxi driver if and only if x_8 is a carpenter can be inferred via the universal biconditional introduction rule.