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: There is at least one z for which z will not read a book. For all z, z will read a book if and only if z will play squash. For all z, z will play squash or z is a taxi driver.
For all z, if z reads a book, then z is playing squash can be inferred via the universal biconditional elimination rule. For all z, if z plays squash, then z is reading a book can be inferred via the universal biconditional elimination rule. There is at least one z for which z will not play squash can be inferred via the existential biconditional elimination rule.