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_6, x_6 is a police officer. There is at least one x_6 for which x_6 is bored. For all x_6, if x_6 were a police officer, then x_6 is a cashier. For all x_6, x_6 will drive a car.
For all x_6, x_6 is a cashier can be inferred via the universal modus ponens rule. For all x_6, x_6 is a police officer and x_6 will drive a car can be inferred via the universal conjunction rule. For all x_6, x_6 will drive a car and x_6 is a police officer can be inferred via the universal conjunction rule. There is at least one x_6 for which x_6 is bored and x_6 is a police officer can be inferred via the existential conjunction rule. There is at least one x_6 for which x_6 is bored and x_6 will drive a car can be inferred via the existential conjunction rule. There is at least one x_6 for which x_6 is a police officer and x_6 is bored can be inferred via the existential conjunction rule. There is at least one x_6 for which x_6 will drive a car and x_6 is bored can be inferred via the existential conjunction rule.