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, if x_6 were sad, then x_6 is an electrician. There is at least one x_6 for which x_6 will drive a car or x_6 will make tea. For all x_6, x_6 will not drive a car or x_6 is sad. For all x_6, x_6 is an electrician if and only if x_6 will make tea.
There is at least one x_6 for which x_6 will make tea or x_6 is sad can be inferred via the existential resolution rule. For all x_6, if x_6 were an electrician, then x_6 is making tea can be inferred via the universal biconditional elimination rule. For all x_6, if x_6 makes tea, then x_6 is an electrician can be inferred via the universal biconditional elimination rule.