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, x_10 will drive a car or x_10 will write a letter. For all x_10, if x_10 writes a letter, then x_10 is fast. For all x_10, if x_10 drives a car, then x_10 is fast. For all x_10, x_10 is an electrician.
For all x_10, x_10 is fast can be inferred via the universal disjunction elimination rule.