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 a sailor, then x_10 is cooking. For all x_10, if x_10 makes tea, then x_10 is a musician. For all x_10, x_10 is not a musician. For all x_10, if x_10 were a musician, then x_10 is making tea. For all x_10, if x_10 cooks, then x_10 is a sailor. For all x_10, x_10 is a sailor if and only if x_10 will make tea.
For all x_10, x_10 will not make tea can be inferred via the universal modus tollens rule. For all x_10, x_10 is a sailor if and only if x_10 will cook can be inferred via the universal biconditional introduction rule. For all x_10, x_10 will make tea if and only if x_10 is a musician can be inferred via the universal biconditional introduction rule. For all x_10, x_10 is a musician if and only if x_10 will make tea can be inferred via the universal biconditional introduction rule. For all x_10, x_10 will cook if and only if x_10 is a sailor can be inferred via the universal biconditional introduction rule. For all x_10, if x_10 were a sailor, then x_10 is making tea can be inferred via the universal biconditional elimination rule. For all x_10, if x_10 makes tea, then x_10 is a sailor can be inferred via the universal biconditional elimination rule.