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 poor, then x_10 is not an electrician. There is at least one x_10 for which if x_10 were poor, then x_10 is cooking. For all x_10, if x_10 were a bartender, then x_10 is an electrician. For all x_10, if x_10 were an artist, then x_10 is an electrician. For all x_10, x_10 is a bartender or x_10 is an artist. For all x_10, if x_10 cooks, then x_10 is poor.
For all x_10, x_10 is an electrician can be inferred via the universal disjunction elimination rule. There is at least one x_10 for which x_10 is poor if and only if x_10 will cook can be inferred via the existential biconditional introduction rule. There is at least one x_10 for which x_10 will cook if and only if x_10 is poor can be inferred via the existential biconditional introduction rule.