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_10, if x_10 were an office clerk, then x_10 is writing a letter. For all x_10, x_10 will write a letter or x_10 is not a sailor. For all x_10, x_10 will listen to a song or x_10 will take a plane. For all x_10, x_10 will not listen to a song. For all x_10, x_10 is a sailor or x_10 is an office clerk.
For all x_10, x_10 will take a plane can be inferred via the universal disjunctive syllogism rule. For all x_10, if x_10 were a sailor, then x_10 is writing a letter can be inferred via the universal rewriting rule.