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 takes a plane, then x_8 is playing tennis. For all x_8, x_8 will take a plane. For all x_8, x_8 will play tennis or x_8 will not read a book. There is at least one x_8 for which x_8 will work.
For all x_8, x_8 will play tennis can be inferred via the universal modus ponens rule. There is at least one x_8 for which x_8 will work and x_8 will take a plane can be inferred via the existential conjunction rule. There is at least one x_8 for which x_8 will take a plane and x_8 will work can be inferred via the existential conjunction rule. For all x_8, if x_8 reads a book, then x_8 is playing tennis can be inferred via the universal rewriting rule.