Consider the following premises. For all z, if z were a musician, then z is a poet. For all z, z will play tennis if and only if z is a cashier. There is at least one z for which z will play tennis or z is a musician. For all z, if z were a poet, then z is a cashier. Can we infer the following from them? For all z, z is not a cashier.
 From the fact that for all z, z will play tennis if and only if z is a cashier we can infer that for all z, if z plays tennis, then z is a cashier. From the fact that for all z, if z were a musician, then z is a poet, and that for all z, if z were a poet, then z is a cashier we can infer that for all z, if z were a musician, then z is a cashier. Finally, from the fact that for all z, if z plays tennis, then z is a cashier, that for all z, if z were a musician, then z is a cashier, and that there is at least one z for which z will play tennis or z is a musician we can infer that there is at least one z for which z is a cashier, which contradicts that For all z, z is not a cashier. Therefore, the answer is no.