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 works, then x_10 is sad. For all x_10, if x_10 were a sailor, then x_10 is working. For all x_10, x_10 is a sailor or x_10 will not work. For all x_10, x_10 is not sad.
For all x_10, x_10 will not work can be inferred via the universal modus tollens rule. For all x_10, if x_10 were a sailor, then x_10 is sad can be inferred via the universal transitivity rule. For all x_10, if x_10 works, then x_10 is a sailor can be inferred via the universal rewriting rule.