$   -------------- -- -- -- -- -- ----------------------------     $0\times0$                       $0.000000000^{a}$     $0\times0$                       $0.000000000^{a}$     $0\times0$                       $0.000000000^{a}$     $0\times0$                       $0.000000000^{a}$     $0\times0$                   