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 an artist or x_6 will work. For all x_6, if x_6 were a writer, then x_6 is a sailor. There is at least one x_6 for which x_6 is not an artist or x_6 is a writer. For all x_6, x_6 will work if and only if x_6 is a sailor.
There is at least one x_6 for which x_6 will work or x_6 is a writer can be inferred via the existential resolution rule. For all x_6, if x_6 works, then x_6 is a sailor can be inferred via the universal biconditional elimination rule. For all x_6, if x_6 were a sailor, then x_6 is working can be inferred via the universal biconditional elimination rule.