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_7, if x_7 were curious, then x_7 is working. For all x_7, if x_7 were curious, then x_7 is playing squash. For all x_7, if x_7 works, then x_7 is curious. For all x_7, if x_7 plays squash, then x_7 is working. For all x_7, x_7 is not curious.
For all x_7, x_7 will not work can be inferred via the universal modus tollens rule. For all x_7, if x_7 were curious, then x_7 is working can be inferred via the universal transitivity rule. For all x_7, if x_7 works, then x_7 is playing squash can be inferred via the universal transitivity rule. For all x_7, if x_7 plays squash, then x_7 is curious can be inferred via the universal transitivity rule. For all x_7, x_7 is curious if and only if x_7 will work can be inferred via the universal biconditional introduction rule. For all x_7, x_7 will work if and only if x_7 is curious can be inferred via the universal biconditional introduction rule.